If you use roaming profiles on your network, the hard drive will become cluttered with cached copies of the profiles of all users who have ever logged on to the system. If only one or two people log on to the machine, it is not a big problem. However, if 20 people use the same machine on different occasions (even months apart), the profiles are wasteful.
To turn off roaming profile caching, apply the following registry fix:
[HKEY_LOCAL_MACHINESOFTWAREMicrosoft Windows NTCurrentVersionWinlogon] "DeleteRoamingCache"=dword:00000001
Now roaming profiles will be deleted when the user logs out.
Note: Please remember that editing your registry is potentially risky; Always have a verified backup before you begin.