{"id":10298,"date":"2026-01-07T13:52:12","date_gmt":"2026-01-07T18:52:12","guid":{"rendered":"https:\/\/copernic.com\/?p=10298"},"modified":"2026-09-28T02:17:49","modified_gmt":"2026-09-28T06:17:49","slug":"question-from-a-user-ost-files","status":"publish","type":"post","link":"https:\/\/copernic.com\/en\/2026\/01\/07\/question-from-a-user-ost-files\/","title":{"rendered":"Question from A User: OST Files"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">From time to time, we receive a question in our ticketing system that we feel would benefit others. When the question is posted in our forums, the community can read the question and subsequent responses. When it\u2019s via an email, it is purely between the user and the agent. Today\u2019s question is regarding OST files in Email settings.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>&#8220;I<\/strong><strong> went to check the OPTIONS -&gt; \u201cEmail &amp; Organizer,\u201d saw OST files are greyed-out?&nbsp;<\/strong><strong>&#8220;<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"780\" height=\"620\" src=\"https:\/\/copernic.com\/wp-content\/uploads\/2026\/01\/Picture1.png\" alt=\"\" class=\"wp-image-10299\" srcset=\"https:\/\/copernic.com\/wp-content\/uploads\/2026\/01\/Picture1.png 780w, https:\/\/copernic.com\/wp-content\/uploads\/2026\/01\/Picture1-300x238.png 300w, https:\/\/copernic.com\/wp-content\/uploads\/2026\/01\/Picture1-768x610.png 768w\" sizes=\"auto, (max-width: 780px) 100vw, 780px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The files can take some time to adjust, and the box will be greyed out while this area loads. Once loaded, the Add PST file box should be available to use.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If it does not display as expected after loading, this means that it added an OST file by passing by the option &#8220;Add PST file&#8221; of the options of Copernic, but this file is already opened in Outlook and Outlook &#8220;locked&#8221; this file when it is opened.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">To change this, follow the steps outlined below:<br><br>&#8211; In the email options of Copernic,\u00a0select the grayed OST file and click on the button &#8220;Remove PST file&#8221;.<br><il>&#8211; Open the section &#8220;Microsoft Outlook&#8221; in &#8220;Email folders to index&#8221; and check the folders that you wish to index.<\/il>That will index them directly from Microsoft Outlook instead of the file.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>From time to time, we receive a question in our ticketing system that we feel would benefit others. When the question is posted in our forums, the community can read the question and subsequent responses. When it\u2019s via an email, it is purely between the user and the agent. Today\u2019s question is regarding OST files&#8230;<\/p>\n","protected":false},"author":5,"featured_media":8833,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[21],"tags":[],"class_list":["post-10298","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-how-tos"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.8 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Question from A User: OST Files | Copernic<\/title>\n<meta name=\"description\" content=\"OST files are Outlook&#039;s local cache and behave differently from PST files. 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What that means for indexing, and how Copernic handles them.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/copernic.com\/en\/2026\/01\/07\/question-from-a-user-ost-files\/\" \/>\n<meta property=\"og:site_name\" content=\"Copernic\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/CopernicSearch\" \/>\n<meta property=\"article:published_time\" content=\"2026-01-07T18:52:12+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-09-28T06:17:49+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/copernic.com\/wp-content\/uploads\/2024\/05\/disable-certain-file-types.jpeg\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"900\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Tracy McAllister\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@copernic\" \/>\n<meta name=\"twitter:site\" content=\"@copernic\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Tracy McAllister\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/2026\\\/01\\\/07\\\/question-from-a-user-ost-files\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/2026\\\/01\\\/07\\\/question-from-a-user-ost-files\\\/\"},\"author\":{\"name\":\"Tracy McAllister\",\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/#\\\/schema\\\/person\\\/5f698207f075a05ef211ec8063d01e46\"},\"headline\":\"Question from A User: OST Files\",\"datePublished\":\"2026-01-07T18:52:12+00:00\",\"dateModified\":\"2026-09-28T06:17:49+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/2026\\\/01\\\/07\\\/question-from-a-user-ost-files\\\/\"},\"wordCount\":221,\"publisher\":{\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/2026\\\/01\\\/07\\\/question-from-a-user-ost-files\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/copernic.com\\\/wp-content\\\/uploads\\\/2024\\\/05\\\/disable-certain-file-types.jpeg\",\"articleSection\":[\"How Tos\"],\"inLanguage\":\"en\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/2026\\\/01\\\/07\\\/question-from-a-user-ost-files\\\/\",\"url\":\"https:\\\/\\\/copernic.com\\\/en\\\/2026\\\/01\\\/07\\\/question-from-a-user-ost-files\\\/\",\"name\":\"Question from A User: OST Files | Copernic\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/2026\\\/01\\\/07\\\/question-from-a-user-ost-files\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/copernic.com\\\/en\\\/2026\\\/01\\\/07\\\/question-from-a-user-ost-files\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/copernic.com\\\/wp-content\\\/uploads\\\/2024\\\/05\\\/disable-certain-file-types.jpeg\",\"datePublished\":\"2026-01-07T18:52:12+00:00\",\"dateModified\":\"2026-09-28T06:17:49+00:00\",\"description\":\"OST files are Outlook's local cache and behave differently from PST files. 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