{"id":3220,"date":"2026-09-16T00:31:18","date_gmt":"2026-09-15T22:31:18","guid":{"rendered":"https:\/\/itsimple.info\/?p=3220"},"modified":"2026-09-16T00:56:02","modified_gmt":"2026-09-15T22:56:02","slug":"september-2026-windows-updates-breaking-remote-desktop-rdp-how-to-fix-it","status":"publish","type":"post","link":"https:\/\/itsimple.info\/?p=3220","title":{"rendered":"September 2026 Windows Updates Breaking Remote Desktop (RDP) \u2014 How to Fix It"},"content":{"rendered":"\n<div style=\"font-family: Arial, sans-serif; line-height: 1.7;\">\n<p>Microsoft&#8217;s September 8, 2026 Patch Tuesday security updates are causing failures in <strong>Remote Desktop Services (RDS)<\/strong> on Windows Server 2019, 2022, and 2025, as well as on Windows 10\/11 endpoints. Connections typically work fine at first, but after a few hours RDP sessions start hanging, users can&#8217;t log off properly, and the server can become completely unresponsive, sometimes requiring a hard reset.<\/p>\n\n<h3>What&#8217;s actually happening?<\/h3>\n<ul>\n<li>RDP connections get stuck at &#8220;Connecting&#8230;&#8221; and never complete.<\/li>\n<li>Servers freeze on the message &#8220;Please wait for the Remote Desktop Configuration.&#8221;<\/li>\n<li>Logged-in users can&#8217;t disconnect or log off cleanly.<\/li>\n<li>MMC, File Explorer, and even the Windows Update page can also hang.<\/li>\n<\/ul>\n\n<h3>Which updates are responsible?<\/h3>\n<table style=\"width:100%; border-collapse: collapse; text-align: left;\" border=\"1\" cellpadding=\"8\">\n<tbody><tr style=\"background-color:#f2f2f2;\">\n<th>Operating System<\/th>\n<th>KB Number<\/th>\n<\/tr>\n<tr><td>Windows Server 2019<\/td><td>KB5122876<\/td><\/tr>\n<tr><td>Windows Server 2022<\/td><td>KB5122882<\/td><\/tr>\n<tr><td>Windows Server 2025<\/td><td>KB5122871<\/td><\/tr>\n<tr><td>Windows 11 24H2 \/ 25H2<\/td><td>KB5124008<\/td><\/tr>\n<\/tbody><\/table>\n\n<p><em>Important: don&#8217;t uninstall these updates as a permanent fix. They also patch a critical, actively exploited vulnerability (CVE-2026-69525, CVSS 9.8). Removing them fixes the RDP issue but reopens a serious security hole.<\/em><\/p>\n\n<h3>How to fix it \u2014 step by step<\/h3>\n\n<ol>\n<li>\n<strong>Install Microsoft&#8217;s emergency out-of-band update released on September 14, 2026.<\/strong><br>\nThis is the official, complete fix. Note: these updates are currently distributed primarily through the <a href=\"https:\/\/www.catalog.update.microsoft.com\/Home.aspx\" target=\"_blank\" rel=\"noopener\" style=\"color: blue; font-weight: bold;\">Microsoft Update Catalog<\/a> rather than standard Windows Update\/WSUS, so you may need to download and install the package manually. They are cumulative, so there&#8217;s no need to remove the September 8 update first. Find your OS below:\n<ul>\n<li>Windows Server 2019: <strong>KB5129238<\/strong> \u2014 <a href=\"https:\/\/support.microsoft.com\/en-us\/servicing\/os\/windows-10\/2026\/09\/kb5129238-windows-10-1809-update\" target=\"_blank\" rel=\"noopener\" style=\"color: blue; font-weight: bold;\">release notes<\/a><\/li>\n<li>Windows Server 2022: <strong>KB5129237<\/strong> \u2014 <a href=\"https:\/\/support.microsoft.com\/en-us\/servicing\/os\/windows-server\/2026\/09\/kb5129237-windows-server-2022-update\" target=\"_blank\" rel=\"noopener\" style=\"color: blue; font-weight: bold;\">release notes<\/a><\/li>\n<li>Windows Server 2025: <strong>KB5129235<\/strong> \u2014 <a href=\"https:\/\/support.microsoft.com\/en-us\/servicing\/os\/windows-server\/2026\/09\/kb5129235-windows-server-2025-update\" target=\"_blank\" rel=\"noopener\" style=\"color: blue; font-weight: bold;\">release notes<\/a><\/li>\n<li>Windows 11 24H2 \/ 25H2: <strong>KB5129195<\/strong> \u2014 <a href=\"https:\/\/support.microsoft.com\/en-us\/servicing\/os\/windows-11\/2026\/09\/kb5129195-windows-11-24h2-25h2-security-update\" target=\"_blank\" rel=\"noopener\" style=\"color: blue; font-weight: bold;\">release notes<\/a><\/li>\n<\/ul>\n<\/li>\n<li>\n<strong>If you can&#8217;t install the out-of-band update right away, enable the Known Issue Rollback (KIR) via Group Policy.<\/strong><br>\nMicrosoft published an official KIR on September 13, 2026, marking the issue as &#8220;Mitigated.&#8221; This rolls back only the problematic change (a feature flag), while keeping the rest of the September security update \u2014 including its security fixes \u2014 intact. It requires Windows Server \/ Microsoft 365 enterprise licensing that supports Group Policy-based KIR deployment.\n<br><br>\n<strong>KIR rollback IDs by OS:<\/strong>\n<ul>\n<li>Windows Server 2019 \/ Windows 10 1809 (KB5122876): rollback ID <strong>260911_18474<\/strong><\/li>\n<li>Windows Server 2022 (KB5122882): rollback ID <strong>260911_18471<\/strong><\/li>\n<li>Windows Server 2025 (KB5122871): rollback ID <strong>260911_18472<\/strong><\/li>\n<\/ul>\n<strong>Step-by-step deployment:<\/strong>\n<ol type=\"a\">\n<li>Download the KIR policy definition <code>.msi<\/code> package that matches your exact OS version (available from Microsoft Support \/ the release health dashboard entry for this issue). Confirm the filename matches your OS build before proceeding.<\/li>\n<li>Run the <code>.msi<\/code> on a management workstation (or your GPO central store host). This installs the new Administrative Template (ADMX\/ADML) files for the policy.<\/li>\n<li>Copy the extracted ADMX and ADML files into your domain&#8217;s central store: <code>\\\\&lt;yourdomain&gt;\\SYSVOL\\&lt;yourdomain&gt;\\Policies\\PolicyDefinitions\\<\/code> (for a single, non-domain-joined server, you can instead run the MSI locally and use <code>gpedit.msc<\/code>).<\/li>\n<li>Open <strong>Group Policy Management Console<\/strong> and create a new GPO (or edit an existing one) scoped to an OU containing your affected RDS servers.<\/li>\n<li>Edit the GPO and navigate to: <strong>Computer Configuration \u2192 Administrative Templates \u2192 KB&lt;number&gt; Issue &lt;XXX&gt; Rollback \u2192 &lt;your Windows version&gt;<\/strong> (the exact folder name includes the KB number and rollback ID above, e.g. &#8220;KB5122882 260911_18471 Known Issue Rollback&#8221;).<\/li>\n<li>Right-click the policy setting and choose <strong>Edit \u2192 Disabled \u2192 OK<\/strong>. Setting it to <em>Disabled<\/em> is correct \u2014 it disables the problematic feature flag (technically, it clears a DWORD value under <code>HKLM\\SYSTEM\\CurrentControlSet\\Policies\\Microsoft\\FeatureManagement\\Overrides<\/code>), which is what rolls back the bug.<\/li>\n<li>Link the GPO to the correct OU, then on each affected server run <code>gpupdate \/force<\/code> to apply it immediately (or wait for the normal background refresh cycle).<\/li>\n<li>Restart each server. RDS\/TermService restarts as part of the reboot and the deadlock condition should no longer occur.<\/li>\n<\/ol>\n<em>Reference: <a href=\"https:\/\/learn.microsoft.com\/en-us\/troubleshoot\/windows-client\/group-policy\/use-group-policy-to-deploy-known-issue-rollback\" target=\"_blank\" rel=\"noopener\">Microsoft&#8217;s official guide to deploying a Known Issue Rollback via Group Policy<\/a>.<\/em>\n<\/li>\n<li>\n<strong>If KIR isn&#8217;t available either, you can try the temporary registry feature-flag workaround.<\/strong><br>\nNote: this has been reported as unreliable and doesn&#8217;t prevent the issue in all cases \u2014 treat it as a last resort only.\n<\/li>\n<li>\n<strong>Test before wide deployment.<\/strong><br>\nRun the update first on a test server or a non-critical RDS group, including licensing servers and jump servers, and make sure you have an alternate management path (e.g. a cloud console or hypervisor interface) in case something goes wrong.\n<\/li>\n<li>\n<strong>Watch Microsoft&#8217;s Release Health dashboard for further updates,<\/strong> especially if you manage Windows Server 2016 \/ 2012 R2 \/ 2012, which have also been reported as affected.\n<\/li>\n<\/ol>\n\n<p><strong>Bottom line:<\/strong> if your RDS servers haven&#8217;t been patched yet, install the September 14 out-of-band update directly and skip the intermediate steps. If you&#8217;ve already hit the issue, use KIR as an immediate fix until the full update is installed.<\/p>\n\n<\/div>\n\n\n\n<figure class=\"wp-block-pullquote has-vivid-green-cyan-color has-white-background-color has-text-color has-background has-link-color has-large-font-size wp-elements-1\"><blockquote><p><strong>Good Luck<\/strong><\/p><\/blockquote><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Microsoft&#8217;s September 8, 2026 Patch Tuesday security updates are causing failures in Remote Desktop Services (RDS) on Windows Server 2019, 2022, and 2025, as well as on Windows 10\/11 endpoints. Connections typically work fine at first, but after a few hours RDP sessions start hanging, users can&#8217;t log off properly, and the server can become [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22,4,12,1,14],"tags":[],"class_list":["post-3220","post","type-post","status-publish","format-standard","hentry","category-security","category-tech","category-tutorials","category-uncategorized","category-windows"],"_links":{"self":[{"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/posts\/3220","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/itsimple.info\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3220"}],"version-history":[{"count":5,"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/posts\/3220\/revisions"}],"predecessor-version":[{"id":3226,"href":"https:\/\/itsimple.info\/index.php?rest_route=\/wp\/v2\/posts\/3220\/revisions\/3226"}],"wp:attachment":[{"href":"https:\/\/itsimple.info\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3220"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/itsimple.info\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3220"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/itsimple.info\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3220"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}