Immidio's Benny Tritsch (we also know him as one of a handful of people who've presented at all eight BriForums!) has posted a white paper entitled "Things You Always Wanted to Know About Windows Profile Management" today on his blog. During BriForum last month, Benny, Kevin Goodman, and Shawn Bass gave a similar presentation with the goal of getting all the information out in the open at one time, rather than listening to fragments here and there. This white paper builds on that session in an attempt to get it all down on paper. In it, he talks about:
- How Windows profiles work (both v1 profiles of anything pre-Windows 2008 & Vista, and v2, which are used in Windows 2008/Vista and beyond)
- The headaches that profiles can introduce
- Solutions for these headaches that are provided by Microsoft, including folder redirection and migrating between v1 and v2 profiles
- A detailed overview of the two prevalent third-party profile management techniques--Profile Streaming and Profile Segmentation
Here's an excerpt from the white paper:
If a user profile is corrupted or if it grew to an unmanageable size, it may become necessary to delete it. But this is not as simple as it seems to be. In Windows Vista, Windows 7 and Windows Server 2008 (including R2), deleting a user profile in the %USERPROFILE% folder results in an error message the next time the user logs on, saying that he was logged on using a temporary profile. The bad news is that upon logoff a temporary profile is deleted and all personal profile data is lost. Using temporary profiles in such a case can be seen as an emergency procedure initiated by Windows when the user profile cannot be loaded, but resulting in an undesired system behavior. All this is due to the fact that Windows keeps track of local profiles in the registry key HKLM \SOFTWARE \Microsoft \Windows NT \CurrentVersion \ProfileList. For each profile a subkey with the name set to the profile owner’s SID is maintained in this list, which is keeping track of the corresponding profile directories. Before creating the temporary profile, Windows renames the original ProfileList subkey to SID.bak.
Windows XP and Windows Server 2003 are more simplistic here. If a ProfileList registry subkey exists but the corresponding profile path is not accessible, they simply create a new local profile. As a result the data in the ProfileList key is overwritten, making the original profile useless without logging a corresponding error message in the Windows event log. For proper profile clean-up it is recommended to open the control panel applet “System Properties” (by running sysdm.cpl) and deleting the profile from there.
At this point you may ask yourself why Microsoft does not completely change the way profiles are working. The primary reason is compatibility. For all their operating system modifications and enhancements, Microsoft needs to make sure that they work for a large range of users, applications and computers. User profiles are such a critical component hooking into so many other operating system components that the underlying architectural concepts cannot be changed so easily. This is why there is enough room for several third-party vendors providing user profile management solutions addressing specific technical challenges or market segments.
Thanks, Benny, for putting together this objective look at Windows profile management. This is sure to be valuable to anyone who needs a little direction when making a profile management decision. In case you missed the link, you can download the white paper here.