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<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1"> <title>Error: Socket bind failed on local address - SparkLabs</title> <link href="/static/css/bootstrap.min.css" rel="stylesheet"> <link href="/static/css/sl_styles.css" rel="stylesheet">   <link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png"> <link rel="icon" type="image/png" sizes="32x32" href="/favicon-32x32.png"> <link rel="icon" type="image/png" sizes="16x16" href="/favicon-16x16.png"> <link rel="mask-icon" href="/safari-pinned-tab.svg" color="#5bbad5"> <meta name="msapplication-TileColor" content="#da532c"> <meta name="theme-color" content="#ffffff"> <link href="/static/css/lity.min.css" rel="stylesheet"> <script src="/static/js/moment.min.js"></script> <link href="/blog/feed/" rel="alternate" title="SparkLabs Blog" type="application/atom+xml"> </head> <body> <div class="sl_header_background_generic" id="slheader"> <nav class="navbar navbar-default bs-docs-nav"> <div class="container"> <div class="navbar-header"> <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar"> <span class="sr-only">Toggle navigation</span> <span class="icon-bar"></span> <span class="icon-bar"></span> <span class="icon-bar"></span> </button> <div style="position: relative;height:50px;"> <a class="navbar-brand" href="/">SparkLabs</a> </div> </div> <div id="navbar" class="navbar-collapse collapse"> <ul class="nav navbar-nav navbar-right"> <li class="dropdown"> <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Products <span class="caret"></span></a> <ul class="dropdown-menu dropdown-menu-left"> <li><a href="/viscosity/">Viscosity</a></li> </ul> </li> <li><a href="/blog/">Blog</a></li> <li><a href="/company/">Company</a></li> <li><a href="/support/">Support</a></li> </ul> </div> </div> </nav>  <div class="container sl_header"> <div class="row"> <div class="col-md-12"> <h1 class="sl_headertext">App <span style="font-weight: 400;">Support.</span></h1> <h1 class="sl_subheadertext">We're here to help.</h1><br /> </div> </div> </div> </div>  <div class="content">  <div class="sl_row_gradient"> <div class="container bs-docs-container"> <div class="row sl_paddedrow"> <div class="col-md-12"> <ol class="breadcrumb"><li><a href="/support/kb/">Knowledge Base</a></li><li><a href="/support/kb/category/common-openvpn-errors/">Common OpenVPN Errors</a></li><li class="active">Error: Socket bind failed on local address</li></ol><br /> </div> <div class="col-md-8"> <h3 class="sl_section_header" id="error-socket-bind-failed-on-local-address">Error: Socket bind failed on local address</h3> <div class="sl_article"><p>OpenVPN connections can be configured to bind to a local address and/or port number when connecting. Binding can be thought of as attaching to a fixed address and port number on the local computer. While fixed binding is needed for the OpenVPN server and for site-to-site connections, it's typically undesired for normal client VPN connections. </p><p>If you're seeing a "TCP/UDP: Socket bind failed on local address" error message in the OpenVPN log, it means your VPN connection is configured to bind to a fixed local address and/or port number, and that this address/port number is unavailable. This can normally be resolved by turning off binding like so: </p> <ol><li> Open Viscosity's Preferences window and make sure the Connections toolbar icon is selected. </li><li> Select your connection and click the Edit button. </li><li> Click the Options tab. </li><li> Tick the "No Bind" checkbox and click the Save button. </li></ol> <p>If you're trying to connect two VPN connections simultaneously, and you receive a "TCP/UDP: Socket bind failed on local address: Address already in use" error message for the second connection, it means that both VPN connections are configured to bind to the same local port number (which isn't possible). Enabling the "No Bind" option for both connections will typically allow both connections to connect. </p></div> </div> <div class="col-md-4" role="complementary"> <nav class="bs-docs-sidebar hidden-print hidden-xs hidden-sm"> <h4 style="padding-left:18px;">Contents</h4> <ul class="nav bs-docs-sidenav"> <li><a href="#error-socket-bind-failed-on-local-address">Error: Socket bind failed on local address</a> </li> </ul> <a class="back-to-top" href="#top">Back to top</a> </nav> </div> </div> </div> </div>  <script src="/static/js/jquery-3.3.1.min.js"></script> <footer class="bs-docs-footer">  <div class="contact-bar"> <div class="container"> <div class="row vertical-align sl_paddedcell_top"> <div class="col-xs-1"></div> <div class="col-xs-2 text-center"> <i id="icons8-search" class="icons8-search contact-icon" style="font-size:54px;padding-left:5px;"></i> </div> <div class="col-xs-7"> <h3 style="color:#fff;">Search Knowledge Base</h3> <p style="color:#fff;" class="text-justify">Search our knowledge base for guides and documentation.</p> <form id="kbsearch" name="kbsearch" method="post" action="/support/kb/search/"> <div class="input-group"> <input name="query" type="text" class="form-control" placeholder="Search for..."> <span class="input-group-btn"> <button class="btn btn-default" type="submit">Search</button> </span> </div> </form> </div> </div> </div> </div>   <div class="sl_row_gradient"> <div class="container"> <div class="row sl_paddedrow"> <br /> <div class="col-md-6 text-left"> <div class="list-group"> <li class="list-group-item"><h4>Other Articles In This Category</h4></li> <a href="/support/kb/article/error-auth-received-control-message-auth_failed/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: AUTH: Received control message: AUTH_FAILED</a> <a href="/support/kb/article/error-cannot-load-certificate-file-cert-crt/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Cannot load certificate file cert.crt</a> <a href="/support/kb/article/error-connection-name-could-not-be-connected/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Connection Name Could Not Be Connected</a> <a href="/support/kb/article/error-inactivity-timeout-ping-restart/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Inactivity timeout (--ping-restart)</a> <a href="/support/kb/article/error-insecure-signature-digest-detected/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Insecure Signature Digest Detected</a> <a href="/support/kb/category/common-openvpn-errors/" class="list-group-item"><span class="badge">25</span><span class="glyphicon glyphicon-menu-right" aria-hidden="true"></span>   View All</a> </div> </div> <div class="col-md-6"> <div class="list-group"> <li class="list-group-item"><h4>Related Articles</h4></li> <a href="/support/kb/article/error-auth-received-control-message-auth_failed/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: AUTH: Received control message: AUTH_FAILED</a> <a href="/support/kb/article/error-cannot-load-certificate-file-cert-crt/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Cannot load certificate file cert.crt</a> <a href="/support/kb/article/error-connection-name-could-not-be-connected/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Connection Name Could Not Be Connected</a> <a href="/support/kb/article/error-inactivity-timeout-ping-restart/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Inactivity timeout (--ping-restart)</a> <a href="/support/kb/article/error-insecure-signature-digest-detected/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Insecure Signature Digest Detected</a> <a href="/support/kb/article/error-private-key-password-verification-failed/" class="list-group-item"><span class="glyphicon glyphicon-asterisk" aria-hidden="true"></span>   Error: Private key password verification failed</a> </div> </div> </div> </div>  </div>  <div style="background-color:#34373a;"> <div class="container"> <div class="row footer_twitter_row"> <div class="col-md-1"> <img src="/static/img/bsky-logo.svg" height=22px style="opacity:0.4;margin-top:14px;" /> </div> <div class="col-md-9"> <p style="color:#bbb;">Follow us on Bluesky <a href="https://bsky.app/profile/sparklabs.com"> @sparklabs.com </a> <span style="color:#666;"> — </span> <span style="color:#bbb;">Viscosity 1.11.4 is now available for macOS! 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