How do I use long path names ("\\?\UNC\...") with Server 2008 roaming profiles?

Question

Hey folks!
I administrate a Windows Server 2008 R2 SP1 Domain with about 40 users on
Windows 7 SP1 clients. Because the users often switch between the many PCs, I am using Roaming Profiles which tend to produce errors with different application-specific paths and files inside the users profiles.
As one of many example, our standard mail application Thunderbird produces paths and files according to folders/subfolders and mails in a user's mailbox. Another one is Microsoft Office's Auto Recovery files which reside in a user's profile and can
get very long.
These paths and filenames often extend the allowed max. path of about 256 characters, when (on log on or off) the synchronization process between the client and the server takes place, leading to errors in the event log and a notification to the user about
the conflict:
"Event ID 1509 - Windows cannot copy file \\server\share\users\user123.v2\AppData\Roaming\looooong to location C:\Users\user123\AppData\Roaming\looooong. DETAIL - The filename or extension is too long."
In the long run this leads to different file versions on different clients which - in the case of Thunderbird - leads to missing mails.
After extensive searches and lectures of forums - including this - I haven't found a solution for this problem.
So my question is if there's a way to use the extended max path with roaming profiles and if so how do I get it to work?
I tried changing the profile path of a test user in the Active Directory user preferences from "\\server\share\profiles\test_user" to something like "\\?\UNC\server\share\profiles\test_user" without any changes in the system's behavior.
Also I think that because this is such a fundamental problem somebody must have come up with a solution for it...
Thanks in advance,
Nico

Answer 1

Hi,
Thanks for your posting.
The Event 1509 can happen if the destination path of the users profile is on a server with a long name and share folder name. For detail information, please refer to:
User profile cannot be loaded with Event ID 1509, DETAIL - The filename or extension is too long
http://blogs.technet.com/b/win7/archive/2011/02/15/user-profile-cannot-be-loaded-with-event-id-1509-detail-the-filename-or-extension-is-too-long.aspx
User profile cannot be loaded with Event ID 1509, DETAIL - The filename or extension is too long
http://support.microsoft.com/kb/2536571
Hope this helps.
Regards.
Vivian Wang
TechNet Community Support