Whenever we see capacity issues on system drive we find some of the older profiles consuming more space, then we try deleting old profiles on the servers for the user accounts which does not exist anymore in the environment.
Whenever a user logs onto a Windows computer, a user profile folder is created for that user under C:\Documents and Settings on windows 2003 servers and C:\users on windows 2008 servers.
If you want to delete any of these user profiles, don’t simply delete the C:\Documents and Settings\username folder for that user as it leaves the registry settings for that profile intact and this can confuse the profile service and cause unpredictable results. Some times improper deletion of profiles will cause lot of orphaned registry keys left out in the ProfileList
The right way of deleting a user profile is to use the profile applet, which is accessible from the advanced tab of the System applet in Control Panel.
Select the profile name and click on delete button to delete the selected profile
Registry path for profiles list:
Note: The profile folder cant be deleted in two conditions, First the user is logged into to the server using the profile which we are trying to delete and second one is the profile folder is being accessed by some process/application.