Forced to update your MSN messenger by windows ? Fight back - Solution here
You can avoid the nag by reshacking the msnmsgr.exe file and changing the version from x.x.xxxx to 15.4.3555,0308
This will allow u to use old version and it thinks I u have the latest one
You need to use a program called Resource Hacker to modify the build number of Windows Live Messenger
Resource Hacker br