diff --git a/NEWS b/NEWS
index cc1d7bc18..66519cecb 100644
--- a/NEWS
+++ b/NEWS
@@ -17,6 +17,7 @@ Bug fixes
  - [web] fixed folder export when XSRF validation is enabled (#4502)
  - [web] don't encode filename extension when exporting folders
  - [web] fixed download of HTML body parts
+ - [web] catch possible exception when registering mailto protocol
  - [core] don't always fetch the sorting columns
  - [eas] strip '<>' from bodyId and when forwarding mails
  - [eas] fix search on for Outlook application (#4605 and #4607)
diff --git a/UI/WebServerResources/js/Mailer/Mailer.app.js b/UI/WebServerResources/js/Mailer/Mailer.app.js
index d1e7aa14a..2790ef600 100644
--- a/UI/WebServerResources/js/Mailer/Mailer.app.js
+++ b/UI/WebServerResources/js/Mailer/Mailer.app.js
@@ -145,7 +145,10 @@
     // Try to register SOGo has an handler for mailto: links
     if (navigator && navigator.registerProtocolHandler) {
       var mailtoURL = window.location.origin + window.ApplicationBaseURL + 'UIxMailPopupView#!/Mail/0/INBOX/new?%s';
-      navigator.registerProtocolHandler('mailto', mailtoURL, 'SOGo');
+      try {
+        navigator.registerProtocolHandler('mailto', mailtoURL, 'SOGo');
+      }
+      catch (e) {}
     }
   }