80048820 is a cryptic, but very common, error message issued by MSN Messenger when it is unable to sign in.

Unfortunately, there are many possible causes of error 80048820. This is somewhat of a generic error, which can make it very difficult to troubleshoot.

Listed below are the most common fixes for the 80048820 error.

Check that the MSN Servers are Working

Before troubleshooting your system, check the MSN Messenger Server Status page to ensure that the MSN Messenger servers are operating correctly.

Check your System Date and Time

Open your system clock by double-clicking the clock on your system toolbar and make certain that the date and time are correct.

Check your Proxy Settings

Invalid proxy settings can sometimes cause the 80048820 error. The difficulty is often determining what the correct proxy settings for your next are. For most networks, the correct setting is to not use a proxy server at all.

  • Open Internet Explorer
  • Open the menu
  • Select the menu item
  • Open the tab

    • If you connect to the Internet using a Dial-up or VPN connectio, click the approriate connection and then click the button
    • If you connect to the Internet using a broadband connection, click the button

  • In the window that opens, configure the correct settings for your proxy:

    • If you do not use a proxy server, uncheck "Use a proxy server…"
    • If you use a manually configured proxy server, check "Use a proxy server…" and make certain that the Address and Port information are correct
    • If you use an automatically detected proxy server, check "Automatically detect settings"
    • If you use an automatically configured proxy server, check "Use automatic configuration script" and enter the address of the script
  • Click the button
  • Click the button

Ensure that SOFTPUB.DLL is Registered

The steps to register SOFTPUB.BLL are:

  • Click the button
  • Click the button
  • Type regsvr32 softpub.dll
  • Click the button
  • Restart MSN Messenger

Download the Latest MSN Messenger

Microsoft has released several patches to help reduce the number of 80048820 errors.

Visit Microsoft to download the latest version of MSN Messenger.

Reinstall Norton Internet Security

Some users have reported that this error can be caused by Norton Internet Security.

For those users, removing and reinstalling Norton Internet Security repaired the issue.

Reinstall Internet Explorer

Some users have reported that this error can be caused by Internet Explorer.

For those users, removing and reinstalling Internet Explorer repaired the issue.

Check the MTU Settings on your Router

The last recommended fix is to change the MTU (Maximum Transmission Unit) size on your router to 1,400 bytes.

Note that changing the MTU on your network can reduce performance for you entire Internet connection. If you are at this point, you might be better off switching to another MSN Messenger compatible instant messaging client, such as Pidgin, Miranda, Psi, Admium, or Trillian.