User Profiles – Location, Location, Location

When a user logs on, regardless of whether they have a local, roaming, mandatory (or even no) profile, they will have a folder created in the location specified under HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\ProfilesDirectory – by default this is %SystemDrive%\Users.

For the majority of cases this will be C:\Users, and there are a couple of things to note about changing this:

1. It is not supported to change this by editing the registry after installing Windows – the supported method is to set the <ProfilesDirectory> property in the unattended setup XML file

2. If this is changed to point to a different volume, then the VirtualStore (registry and file virtualization) will not work

So basically, don’t do it :)
(See KB949977 )

If space on the system volume is a problem, there are other possible options available:

1. On a per-user, per-library basis, set the Location property to point to a different path

2. Use folder redirection via group policy

3. Move the page file to another volume (to be able to get memory dumps, you can use DedicatedDumpFile )

Do not go deleting anything under WinSxs to reclaim space either - while you might think you do not need it, there is no way of knowing if the system might later…

If your environment is a Terminal Server or Remote Desktop Services Session Host, then the space used by profiles can become quite large indeed (a good reason to use mandatory profiles or folder redirection) – there are a couple of group policy settings which can help alleviate the problem:

1. “Delete cached copies of roaming profiles” (See KB274152)

2. “Delete user profiles older than a specified number of days on system restart” (See KB940017)