Hi,
I wasn't sure where to post this one, but here goes anyway.
Up until today MSN has worked fine on this PC. Now all I get is a small window with the message "Signing into .NET Messenger service failed because the service is temporaraly unavailable. Please try again later".
I have tried loads of times but to no avail. My daughter is able to connect on her laptop as is my son on his X Box.
In Network connections the device manager says "MSN unavailable. Device missing".
I have checked firewall exceptions and MSN is checked.
What I don't understand is why only this PC is affected and not my kids.
Any ideas please.

By any chance, did you block it by accident? With Internet Explorer opened, go to Tools, Delete Browsing History, in the next window click Delete Files, Delete Cookies, and Delete Files.

Check out the following for information:

Reinstallation caused problems - Tech Support Guy Forums

VMware Communities: Internet Explorer no longer connects ...