Error message: Reason Unknown - TeamViewer Support
<main> <article class="userContent"> <h3></h3><h2 data-id="general">General</h2><div class="blockquote"><div class="blockquote-content"><p class="blockquote-line"><em>This article applies to all TeamViewer users who have not upgraded the TeamViewer software to the latest version and see the error message: "Unable to connect - Reason unknown".</em></p></div></div><p>TeamViewer recommends that all users download and start using the latest version of TeamViewer on all supported operating system platforms.</p><p>When you see a pop-up offering you to <strong>Update Now</strong>, please check the version of the TeamViewer software you are currently using, and immediately update to the <a href="https://www.teamviewer.com/download" rel="nofollow noreferrer ugc">latest version of TeamViewer</a>.</p><p><br></p><h3 data-id="-1"></h3><h2 data-id="check-teamviewer-version">Check TeamViewer version</h2><ul><li><strong>Windows</strong>: TeamViewer --> Help --> About TeamViewer --> Version</li><li><strong>macOS</strong>: TeamViewer --> About TeamViewer --> Version</li><li><strong>Linux</strong>: TeamViewer --> Help --> About TeamViewer --> Version</li><li><strong>Android</strong>: TeamViewer --> Settings --> Version</li><li><strong>iOS</strong>: TeamViewer --> Settings --> Advanced Settings --> Version Information</li></ul><p>At the same time, please check the compatibility of operating systems and software versions: <a href="https://community.teamviewer.com/English/kb/articles/24141-which-operating-systems-are-supported" rel="nofollow noreferrer ugc">Supported operating systems</a>.</p><p><br></p><h3 data-id="-2"></h3><h2 data-id="solution">Solution</h2><p>When you see the error messages in TeamViewer with <strong>Reason Unknown</strong>, and the connection cannot be established, please download and update TeamViewer to the latest version.</p><p><br></p><h3 data-id="-3"></h3><h2 data-id="windows-linux-and-macos">Windows, Linux and macOS</h2><p>When the TeamViewer software pops up with an error: <strong>Unable to connect - Reason unknown</strong>, please update TeamViewer to the latest available version.</p><p><br></p><div class="embedExternal embedImage display-large float-none"> <div class="embedExternal-content"> <a class="embedImage-link" href="https://us.v-cdn.net/6032394/uploads/DAJ6NKUJHYGM/image.png" rel="nofollow noreferrer noopener ugc" target="_blank"> <img class="embedImage-img" src="https://us.v-cdn.net/6032394/uploads/DAJ6NKUJHYGM/image.png" alt="image.png" height="170" width="489" loading="lazy" data-display-size="large" data-float="none"></img></a> </div> </div> <p><br></p><ul><li>On the TeamViewer software, click Help -> Check for new version to complete the software update</li><li><a href="https://www.teamviewer.com/en/download/windows/" rel="nofollow noreferrer ugc">Download the latest version of TeamViewer</a></li></ul><p> </p><h3 data-id="-4"></h3><h2 data-id="mobile-devices-android-and-ios">Mobile devices - Android and iOS</h2><p>When the TeamViewer remote control app shows the following error:</p><p><strong>Android</strong>: Could not connect to partner</p><div class="embedExternal embedImage display-medium float-none"> <div class="embedExternal-content"> <a class="embedImage-link" href="https://us.v-cdn.net/6032394/uploads/MLZMFGSJVVT8/image.png" rel="nofollow noreferrer noopener ugc" target="_blank"> <img class="embedImage-img" src="https://us.v-cdn.net/6032394/uploads/MLZMFGSJVVT8/image.png" alt="image.png" height="123" width="396" loading="lazy" data-display-size="medium" data-float="none"></img></a> </div> </div> <p><br></p><p><strong>iOS</strong>: Unable to connect - A connection could not be established. Reason unknown</p><div class="embedExternal embedImage display-large float-none"> <div class="embedExternal-content"> <a class="embedImage-link" href="https://us.v-cdn.net/6032394/uploads/ORY99B8P9JMN/image.png" rel="nofollow noreferrer noopener ugc" target="_blank"> <img class="embedImage-img" src="https://us.v-cdn.net/6032394/uploads/ORY99B8P9JMN/image.png" alt="image.png" height="410" width="450" loading="lazy" data-display-size="large" data-float="none"></img></a> </div> </div> <p><br></p><p>Please update the TeamViewer remote control app to the latest version via your app store.</p><ul><li><strong>Android</strong>: <a href="https://www.teamviewer.com/en/download/android/" rel="nofollow noreferrer ugc">Download</a> the latest version of TeamViewer remote control</li><li><strong>iOS</strong>: <a href="https://www.teamviewer.com/en/download/ios/" rel="nofollow noreferrer ugc">Download</a> the latest version of TeamViewer remote control<code class="code codeInline" spellcheck="false" tabindex="0"> </code></li></ul><p><br></p> </article> </main>
