11 things to try if you see error 80048820 when trying to sign into Messenger

If you see error 80048820 when you try to sign in to Messenger, try the following steps:

Make sure your PC's date and time settings are correct
Set Internet Explorer security settings to use SSL
Re-register the security.dll files
Scan your PC for viruses
Check your firewall and router settings to make sure that your firewall isn't blocking port 443
Clear the Messenger proxy settings
Reset the proxy server settings for Internet Explorer
Disconnect or bypass your router to make sure your router settings aren't blocking your connection to Messenger
Make sure Internet Explorer isn't set to work offline
Check and clear the entries in the Hosts file
Clear the DNS cache

read how to do each of these for Windows 7, Widows Vista and Windows XP Messenger sign-in error 80048820

Rob

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