MSN 7.5 has a solution for 80048820 error

                  1. Select tcp, socks and proxy server in msn tool-option-connection-advanced settings;

2. Do not set all options of ie tool-option-LAN setting;
< BR>3. Is the “Date/Time Attribute” on your computer set correctly: Double-click the time to check if the date and time are set correctly.

4. If your account number and password are not stored in MSN, you need to make sure you enter the account number and password are correct (note the case suffix letters and accounts).

5. Disable the "Auto detect" setting in your browser. For Internet Explorer users, click the IE Tools menu, click Internet Options, click the Connections tab, click the LAN Settings button, and then clear the Automatically detect settings box.

6. Clear IE cache and cookies: Open Internet Explorer browser, press the Tools menu, then select "Internet Options", click the "Delete Files" button and the "Delete Cookies" button.

7. Check IE security settings: Open Internet Explorer browser, press the Tools menu, select "Internet Options", select "Advanced", drag the scroll bar to the security selection, and confirm "Check Server Certificate Revocation" Not selected, and confirmed that "Use SSL 2.0" and "Use SSL 3.0" were selected. Then press "OK".

8. Click "Start" - "Run", then type:
regsvr32 softpub.dll
regsvr32 mssip32.dll
regsvr32 initpki.dll (longer time) then press "determine".

9. check for errors proxy server settings. On the MSN Messenger Tools menu, click Options. On the Connections tab, make sure you clear the "I use a proxy server" checkbox.

10. Firewall and third-party applications may affect connect to MSN Messenger. You can disable the application, firewall, or open the firewall and try to connect to the .Net Messenger Service.

11. If you are using an ICS or router for your local area network, you may need to adjust some settings or update the hardware/firmware drivers.

12. If your Passport is not recognized, please log in to the Passport site at http://www.passport.com and confirm that it is identifiable there. If you can be identified there, but you still can't log in to the .NET Messenger Service, it's possible that the message server temporarily shuts down the maximum traffic that is being maintained or reaches the Internet (during peak usage periods). Please try again later. You can also check the server status page to see the latest information about the server.

13. If the Passport site is still unrecognizable, please go here: http://memberservicesnet.passport.com/memberservice.srf and select: "I forgot my password".