I came to know this method, when I saw one of the IT techs use it to troubleshoot some Internet connectivity issues.
To clear any saved username/passwords (i.e. Internet Explorer, Windows Explorer etc) in Microsoft Windows, do the following
- Click Start –> Run, and type in
control keymgr.dll - Delete any entries you want to from the list
- Click on close
I tried this on Windows XP and Vista.