{"id":1691,"date":"2026-02-14T17:15:25","date_gmt":"2026-02-14T17:15:25","guid":{"rendered":"https:\/\/www.gaintools.com\/how\/?p=1691"},"modified":"2026-02-14T17:15:25","modified_gmt":"2026-02-14T17:15:25","slug":"fix-exchange-server-ost-cannot-be-opened-error","status":"publish","type":"post","link":"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/","title":{"rendered":"How to Fix Exchange Server OST Cannot Be Opened Error (Quick Methods)"},"content":{"rendered":"<p>Exchange Server OST cannot be opened error is a common Outlook issue that prevents users from accessing mailbox data. This guide explains the main causes and instant solutions to fix this error quickly.<\/p>\n<p>OST or Offline Storage Table is exactly the replica of the mailbox items stored on the Exchange Server. The most important and major attribute of the OST file is that it enables users to work in offline mode. Outlook accounts that sync with MS Exchange Server save the data in the OST file format in the local drive of the users\u2019 systems.<\/p>\n<p>However, when the OST file becomes corrupted or inaccessible, users face errors like Microsoft Exchange Server OST cannot be opened and cannot access mailbox data.<\/p>\n<p><strong>Also read: <\/strong><a href=\"https:\/\/www.gaintools.com\/how\/fix-the-file-username-ost-is-in-use-and-cannot-be-accessed-in-outlook\/\">The File Username.ost is in Use and cannot be Accessed<\/a><\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_79 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Major_Reasons_Behind_Exchange_Server_OST_Cannot_Be_Opened_Error\" >Major Reasons Behind Exchange Server OST Cannot Be Opened Error<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#How_to_Resolve_Exchange_Server_OST_Cannot_Be_Opened_Error\" >How to Resolve Exchange Server OST Cannot Be Opened Error<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Manual_Methods_to_Fix_Exchange_Server_OST_Cannot_Be_Opened_Error\" >Manual Methods to Fix Exchange Server OST Cannot Be Opened Error<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Solution_1_Update_your_Outlook_application\" >Solution 1. Update your Outlook application<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Solution_2_Run_Outlook_in_safe_mode_and_disable_incompatible_add-ins\" >Solution 2. Run Outlook in safe mode and disable incompatible add-ins<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Solution_3_Repair_the_Outlook_program_with_the_Windows_default_repair_utility\" >Solution 3. Repair the Outlook program with the Windows default repair utility<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Solution_4_Disable_Antivirus_and_firewall_applications_in_your_system\" >Solution 4. Disable Antivirus and firewall applications in your system<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Solution_5_Scan_and_repair_the_OST_files_using_the_Inbox_Repair_Tool\" >Solution 5. Scan and repair the OST files using the Inbox Repair Tool<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Professional_Solution_to_Fix_Exchange_Server_OST_Opening_Error\" >Professional Solution to Fix Exchange Server OST Opening Error<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Conclusion\" >Conclusion<\/a><ul class='ez-toc-list-level-4' ><li class='ez-toc-heading-level-4'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/#Frequently_Asked_Questions\" >Frequently Asked Questions<\/a><\/li><\/ul><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"Major_Reasons_Behind_Exchange_Server_OST_Cannot_Be_Opened_Error\"><\/span><strong>Major Reasons Behind Exchange Server OST Cannot Be Opened Error<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Let us understand the possible reasons behind this error. This will help you to figure out the perfect solution to fix the error message. Here is the list of major reasons:<\/p>\n<ul>\n<li>Poor synchronization between Outlook and Exchange Server<\/li>\n<li>Internal damage and data inconsistency cause the OST file to become corrupted<\/li>\n<li>Installed antivirus application or firewall systems that restrict Outlook from accessing it<\/li>\n<li>Large size of the OST file results in performance issues<\/li>\n<li>An incompatible or outdated version of Outlook is the cause behind this<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"How_to_Resolve_Exchange_Server_OST_Cannot_Be_Opened_Error\"><\/span>How to Resolve Exchange Server OST Cannot Be Opened Error<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>As we discussed above, the error arises due to many reasons, making it tough to fix this problem. Therefore, here we suggest some manual ways that help you deal with the error.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Manual_Methods_to_Fix_Exchange_Server_OST_Cannot_Be_Opened_Error\"><\/span>Manual Methods to Fix Exchange Server OST Cannot Be Opened Error<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Solution_1_Update_your_Outlook_application\"><\/span><strong>Solution 1. Update your Outlook application<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>In some scenarios, this problem arises due to incompatibility or internal problems. Updating your Outlook application might help you to fix this error and make it accessible again. For updating Outlook, the steps are mentioned below:<\/p>\n<ul>\n<li>Open the Outlook program and head to the <strong>File <\/strong>tab<\/li>\n<li>Tap on <strong>Office account, <\/strong>hit on <strong>Microsoft 365 and Office Updates. <\/strong>Then, place the mouse pointer on the <strong>Update Now <\/strong>button.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-1699 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/1-300x181.webp\" alt=\"\" width=\"665\" height=\"401\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/1-300x181.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/1-768x464.webp 768w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/1.webp 1021w\" sizes=\"auto, (max-width: 665px) 100vw, 665px\" \/><\/p>\n<ul>\n<li>This will start <strong>checking for updates<\/strong> and start downloading them automatically.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-1700 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/2-300x143.webp\" alt=\"\" width=\"403\" height=\"192\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/2-300x143.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/2.webp 490w\" sizes=\"auto, (max-width: 403px) 100vw, 403px\" \/><\/p>\n<ul>\n<li>Now, close and restart Outlook after completing the update to check if the issue is resolved or not.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Solution_2_Run_Outlook_in_safe_mode_and_disable_incompatible_add-ins\"><\/span><strong>Solution 2. Run Outlook in safe mode and disable incompatible add-ins<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Sometimes, installed add-ins can obstruct Outlook performance and be the cause of the &#8220;Exchange OST cannot be opened&#8221; error. To resolve this, you can disable them. Check the steps below for this:<\/p>\n<ul>\n<li>Press Win + R keys together to start the <strong>Run <\/strong>dialog box. Now, enter <strong>Outlook\/safe <\/strong>to open MS Outlook in safe mode.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-1701 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/3-300x154.webp\" alt=\"\" width=\"405\" height=\"208\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/3-300x154.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/3.webp 412w\" sizes=\"auto, (max-width: 405px) 100vw, 405px\" \/><\/p>\n<ul>\n<li>Start <strong>Outlook <\/strong>and tap on <strong>Options.<\/strong><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-1702 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/4-300x234.webp\" alt=\"\" width=\"433\" height=\"337\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/4-300x234.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/4.webp 633w\" sizes=\"auto, (max-width: 433px) 100vw, 433px\" \/><\/p>\n<ul>\n<li>Tap on the <strong>Add-ins <\/strong>section and press the <strong>Go <\/strong>button.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-1703 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/5-300x245.webp\" alt=\"\" width=\"436\" height=\"356\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/5-300x245.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/5-768x628.webp 768w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/5.webp 800w\" sizes=\"auto, (max-width: 436px) 100vw, 436px\" \/><\/p>\n<ul>\n<li>Unmark all the available add-ins and press <strong>OK.<\/strong><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-1704 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/6-300x128.webp\" alt=\"\" width=\"439\" height=\"187\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/6-300x128.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/6.webp 621w\" sizes=\"auto, (max-width: 439px) 100vw, 439px\" \/><\/p>\n<ul>\n<li>Now, restart the Outlook program and enable add-ins one by one to figure out the problematic one. Disable the problematic component and check whether the error is resolved.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Solution_3_Repair_the_Outlook_program_with_the_Windows_default_repair_utility\"><\/span><strong>Solution 3. Repair the Outlook program with the Windows default repair utility<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>To repair installed applications, Windows offers a default repair utility. To fix the Outlook application, you can use this utility. The steps are as follows:<\/p>\n<ul>\n<li>Exit <strong>MS Outlook<\/strong> if running and open the Control Panel<\/li>\n<li>Hit on <strong>Programs and Features <\/strong>under the Control Panel window.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-1705 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/7-300x212.webp\" alt=\"\" width=\"487\" height=\"344\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/7-300x212.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/7-768x542.webp 768w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/7.webp 800w\" sizes=\"auto, (max-width: 487px) 100vw, 487px\" \/><\/p>\n<ul>\n<li>Pick <strong>Microsoft 365 (or Outlook) <\/strong>from the installed programs and tap on the <strong>Change <\/strong>option.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-1706 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/8-300x211.webp\" alt=\"\" width=\"498\" height=\"350\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/8-300x211.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/8-768x540.webp 768w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/8.webp 800w\" sizes=\"auto, (max-width: 498px) 100vw, 498px\" \/><\/p>\n<ul>\n<li>Tap on the <strong>Repair <\/strong>option in the newly opened wizard.<\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-1707 aligncenter\" src=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/9-300x206.webp\" alt=\"\" width=\"300\" height=\"206\" srcset=\"https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/9-300x206.webp 300w, https:\/\/www.gaintools.com\/how\/wp-content\/uploads\/2026\/02\/9.webp 452w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/p>\n<ul>\n<li>This will start the repair process. Now, restart MS Outlook.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Solution_4_Disable_Antivirus_and_firewall_applications_in_your_system\"><\/span><strong>Solution 4. Disable Antivirus and firewall applications in your system<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Antivirus or firewall applications are important to maintain a safe environment within an organization. However, there are cases where these security applications affect Outlook\u2019s performance. To check if these applications are responsible for the error, disable them and check. If the Outlook application works fine after disabling the applications, then clearly, they are responsible for the error. You need to make adjustments that do not affect the functionality of Outlook.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Solution_5_Scan_and_repair_the_OST_files_using_the_Inbox_Repair_Tool\"><\/span><strong>Solution 5. Scan and repair the OST files using the Inbox Repair Tool<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>To fix the \u2018Exchange Server OST file Cannot be Opened\u2019 error, you can try the Inbox Repair Tool, as OST file corruption can be the reason for this. ScanPST.exe or Inbox Repair Tool is inbuilt in Outlook and helps you remove minor corruption errors from OST files &amp; make them accessible again.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Professional_Solution_to_Fix_Exchange_Server_OST_Opening_Error\"><\/span><strong>Professional Solution to Fix Exchange Server OST Opening Error<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>You can\u2019t open an Outlook OST file without resolving the error \u2018Microsoft Exchange Server .ost cannot be opened.\u2019 In this case, you can try manual solutions to resolve the error. However, if these solutions won\u2019t work, what\u2019s next? Generally, the manual solutions resolve this error; however, if your OST file is highly damaged or corrupted, these solutions become ineffective. In this situation, you need to try automated solutions to resolve this error message.<\/p>\n<p>If the OST file becomes severely corrupted, orphaned, or inaccessible, manual methods and ScanPST often fail to repair it completely. In such cases, using a professional OST recovery solution is the most effective way to restore mailbox data and open the OST file without errors.<\/p>\n<p>By using <strong>GainTools <a href=\"https:\/\/www.gaintools.com\/ost\/pst\/\">OST to PST Converter<\/a>, <\/strong>you can easily repair your corrupted or damaged OST files. This efficient program also allows users to export the data from a damaged OST file to a new PST file, so users can open this file. You will get numerous facilities with this program to efficiently handle OST file-related issues.<\/p>\n<p style=\"text-align: left;\">You will find a free demo edition of this program to check its features &amp; functions before investing in it. This application supports all kinds of OST files and helps you fix the error message and make your OST file accessible again by converting its data into a PST file.<\/p>\n<p style=\"text-align: center;\"><a class=\"maxbutton-1 maxbutton maxbutton-download-now\" target=\"_blank\" rel=\"nofollow noopener\" href=\"https:\/\/www.gaintools.com\/dl\/sign\/gainostdemo.exe\"><span class='mb-text'>Download Now<\/span><\/a> <a class=\"maxbutton-2 maxbutton maxbutton-buy-now\" target=\"_blank\" rel=\"nofollow noopener\" href=\"https:\/\/www.gaintools.com\/ost\/order\/\"><span class='mb-text'>Buy Now<\/span><\/a><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Conclusion\"><\/span>Conclusion<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>This guide explains the major causes and effective solutions to fix the Exchange Server OST cannot be opened error. Manual methods help resolve minor issues, but severely corrupted or inaccessible OST files require a professional recovery solution. Using a reliable OST recovery tool allows users to repair damaged OST files and restore mailbox data safely without data loss.<\/p>\n<h4><span class=\"ez-toc-section\" id=\"Frequently_Asked_Questions\"><\/span>Frequently Asked Questions<span class=\"ez-toc-section-end\"><\/span><\/h4>\n<p data-start=\"1253\" data-end=\"1420\"><strong data-start=\"1253\" data-end=\"1315\">Why does the Exchange Server OST fail to open?<\/strong><br data-start=\"1315\" data-end=\"1318\" \/>It occurs due to corruption, synchronization issues, oversized OST files, or Outlook profile problems.<\/p>\n<p data-start=\"1422\" data-end=\"1550\"><strong data-start=\"1422\" data-end=\"1469\">Can the ScanPST tool fix OST file errors?<\/strong><br data-start=\"1469\" data-end=\"1472\" \/>ScanPST can repair minor corruption but cannot fix severely damaged OST files.<\/p>\n<p data-start=\"1552\" data-end=\"1690\"><strong data-start=\"1552\" data-end=\"1590\">How to open an inaccessible OST file?<\/strong><br data-start=\"1590\" data-end=\"1593\" \/>You can use manual methods or a professional OST to PST converter to open inaccessible OST files.<\/p>\n<p data-start=\"1692\" data-end=\"1834\"><strong data-start=\"1692\" data-end=\"1745\">What is the best solution for a corrupted OST file?<\/strong><br data-start=\"1745\" data-end=\"1748\" \/>A professional OST recovery tool is the safest way to repair and recover mailbox data.<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<style id=\"app_ajhbdcgfhlhhmocddefknjjkejcfpbnj_style\">html,\nbody,\nbody:not(.web_whatsapp_com) *,\nhtml body:not(.web_whatsapp_com) *,\nhtml body.ds *,\nhtml body:not(.web_whatsapp_com) div *,\nhtml body:not(.web_whatsapp_com) span *,\nhtml body p *,\nhtml body h1 *,\nhtml body h2 *,\nhtml body h3 *,\nhtml body h4 *,\nhtml body h5 *,\nhtml\n  body:not(.web_whatsapp_com)\n  *:not(input):not(textarea):not([contenteditable=\"\"]):not(\n    [contenteditable=\"true\"]\n  ),\nhtml\n  body:not(.web_whatsapp_com)\n  *[class]:not(input):not(textarea):not([contenteditable=\"\"]):not(\n    [contenteditable=\"true\"]\n  ),\nhtml\n  body:not(.web_whatsapp_com)\n  *[id]:not(input):not(textarea):not([contenteditable=\"\"]):not(\n    [contenteditable=\"true\"]\n  ) {\n  user-select: text !important;\n}<\/p>\n<p>html body *:not(input):not(textarea)::selection,\nbody *:not(input):not(textarea)::selection,\nhtml body div *:not(input):not(textarea)::selection,\nhtml body span *:not(input):not(textarea)::selection,\nhtml body p *:not(input):not(textarea)::selection,\nhtml body h1 *:not(input):not(textarea)::selection,\nhtml body h2 *:not(input):not(textarea)::selection,\nhtml body h3 *:not(input):not(textarea)::selection,\nhtml body h4 *:not(input):not(textarea)::selection,\nhtml body h5 *:not(input):not(textarea)::selection {\n  background-color: #3297fd !important;\n  color: #ffffff !important;\n}<\/p>\n<p>\/* linkedin *\/\n\/* squize *\/\n.www_linkedin_com\n  .sa-assessment-flow__card.sa-assessment-quiz\n  .sa-assessment-quiz__scroll-content\n  .sa-assessment-quiz__response\n  .sa-question-multichoice__item.sa-question-basic-multichoice__item\n  .sa-question-multichoice__input.sa-question-basic-multichoice__input.ember-checkbox.ember-view {\n  width: 40px;\n}\n\/*linkedin*\/<\/p>\n<p>\/*instagram*\/\n\/*wall*\/\n.www_instagram_com ._aagw {\n  display: none;\n}<\/p>\n<p>\/*developer.box.com*\/\n.bp-doc .pdfViewer .page:not(.bp-is-invisible):before {\n}<\/p>\n<p>\/*telegram*\/\n.web_telegram_org .emoji-animation-container {\n  display: none;\n}\nhtml\n  body.web_telegram_org\n  .bubbles-group\n  > .bubbles-group-avatar-container:not(input):not(textarea):not(\n    [contenteditable=\"\"]\n  ):not([contenteditable=\"true\"]),\nhtml\n  body.web_telegram_org\n  .custom-emoji-renderer:not(input):not(textarea):not([contenteditable=\"\"]):not(\n    [contenteditable=\"true\"]\n  ) {\n  pointer-events: none !important;\n}<\/p>\n<p>\/*ladno_ru*\/\n.ladno_ru [style*=\"position: absolute; left: 0; right: 0; top: 0; bottom: 0;\"] {\n  display: none !important;\n}<\/p>\n<p>\/*mycomfyshoes.fr *\/\n.mycomfyshoes_fr #fader.fade-out {\n  display: none !important;\n}<\/p>\n<p>\/*www_mindmeister_com*\/\n.www_mindmeister_com .kr-view {\n  z-index: -1 !important;\n}<\/p>\n<p>\/*www_newvision_co_ug*\/\n.www_newvision_co_ug .v-snack:not(.v-snack--absolute) {\n  z-index: -1 !important;\n}<\/p>\n<p>\/*derstarih_com*\/\n.derstarih_com .bs-sks {\n  z-index: -1;\n}<\/p>\n<p>html\n  body\n  .alc_unlock-pseudo-before.alc_unlock-pseudo-before.alc_unlock-pseudo-before::before {\n  pointer-events: none !important;\n}\nhtml\n  body\n  .alc_unlock-pseudo-after.alc_unlock-pseudo-after.alc_unlock-pseudo-after::after {\n  pointer-events: none !important;\n}\n<\/style>\n","protected":false},"excerpt":{"rendered":"<p>Exchange Server OST cannot be opened error is a common Outlook issue that prevents users from accessing mailbox data. This guide explains the main causes and instant solutions to fix this error quickly. OST or Offline Storage Table is exactly the replica of the mailbox items stored on the Exchange Server. The most important and&#8230;<\/p>\n<p class=\"more-link-wrap\"><a href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/\" class=\"more-link\">Read More<span class=\"screen-reader-text\"> &ldquo;How to Fix Exchange Server OST Cannot Be Opened Error (Quick Methods)&rdquo;<\/span> &raquo;<\/a><\/p>\n","protected":false},"author":3,"featured_media":1709,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[28],"tags":[],"class_list":["post-1691","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-ost-converter"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.2 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Fix Exchange Server OST Cannot Be Opened Error\u2013 Quick Guide<\/title>\n<meta name=\"description\" content=\"Fix Exchange Server OST cannot be opened error with 5 instant solutions. Repair corrupted or inaccessible OST files and recover mailbox data safely.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.gaintools.com\/how\/fix-exchange-server-ost-cannot-be-opened-error\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Fix Exchange Server OST Cannot Be Opened Error\u2013 Quick Guide\" \/>\n<meta property=\"og:description\" content=\"Fix Exchange Server OST cannot be opened error with 5 instant solutions. 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