Replace the cmos battery, and reset the time and date...
Error code 80048820 is a common one with MSN Messenger 7.5 and Windows Live Messenger.
When you start MSN Messenger, you are unable to sign in.
“Sorry, we were unable to sign you in to the MSN Messenger at this time. Please try again later.”
Fix 80048820 MSN (Windows Live Messenger) Error.
-The system clock may be set incorrectly.
-The Dynamic Link Library (DLL) softpub.dll may not be registered on the system. -Internet Explorer may be using an invalid proxy server.
-Double click on the clock in the taskbar and make sure the system clock is set correctly