问题：选择记录用户名后，可是每次开机还是要重新输入用户
解决：
I've found the answer to this annoying problem @ http://messengergeek.spaces.live.com/blog/cns!E3785B1281BBDA1!2883.entry , the culprit Yahoo! Toolbar.
WARNING: the autofix download available there is only for English (language) Windows, using the download for other languages may break configurations for other programs such as Firefox. For other language you have to have to do it manually, following the solution Adam proposes:
You don't actually need to install this app everybody keeps downloading.... All you need to do is change a registry value.
After hours of messing around with RegEdit + Yahoo Messenger + Microsoft's Virtual PC I've found the problem and a solution to why apps like Msn Messenger suddenly can't remember their passwords anymore.
When Yahoo toolbar gets installed it sets the following registry value:
[HKEY_USERS/S-1-5-21-796845957-926492609-725345543-1003/Software/Microsoft/Windows/CurrentVersion/Explorer/User Shell Folders]
AppData = %AppData%
The problem here is AppData should actually be the following
AppData = %USERPROFILE%/Application Data
So when MSN or other apps that use that registry key go to save their data it gets lost.
So the solution is simple, run regedit and go to
[HKEY_USERS/S-1-5-21-796845957-926492609-725345543-1003/Software/Microsoft/Windows/CurrentVersion/Explorer/User Shell Folders]
and set the value AppData to a data value of %USERPROFILE%/Application Data
But instead of Application Data you have to use the expression used in your language, for example in Spanish it is Datos de programa .
I hope this fixes this mess 
PS. I'm not going to install Yahoo! Toolbar anymore, first it messed up my right click in Firefox and then this. Not worth it.