I recently reinstalled Windows 2000 Advanced Server on one file server. When users try to access files on the server either locally or over the network, a message informs them that the files are already in use and to try again later. However, I've confirmed that no one's using the files in question. Furthermore, the problem seems to affect most of the files users try to access. I've reinstalled the OS, reformatted the volume, and restored the data from a backup tape with no luck. Can you help?

When one organization I know experienced similar problems with file access, this sequence of events had occurred:

  1. Remote Installation Services (RIS) was originally installed on the server.
  2. RIS was configured to include the volume with the server's shared files.
  3. The OS was later reinstalled without RIS.

Your scenario might be similar. The problem results from the way that RIS's Single Instance Storage (SIS) service modifies extended NTFS file attributes on the RIS/SIS-enabled volumes. If you first let SIS manage a volume, later reinstall the OS without RIS/SIS, and attempt to access the already SIS-modified files on that volume, you receive in-use errors. Your restore from backup solution probably didn't work because the backup contained the RIS installation (only a backup made before RIS was installed could solve the problem).

To solve the problem, you need to reinstall RIS on the server, which will in turn reinstall the SIS service. After SIS is present, you should be able to access the files. You can also get rid of RIS on the server after you reinstall, although SIS will remain on the system. To avoid situations such as yours, when you install RIS, you should create a separate volume designated for RIS images and let RIS/SIS manage that volume only. If you want to completely remove SIS from the volume, you'll need to take several steps including mapping the affected drive to a network drive letter and subsequently backing it up through the network drive letter (doing so forces SIS to expand all the files on the volume in a non-SIS-specific format). You'll find the steps outlined in the Microsoft article "HOW TO: Uninstall Remote Installation Services and Single Instance Storage," (Q299873, http://support.microsoft.com).