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When I attempt to restore to any restore point, I receive a "restore failed" message, although my system has not changed. I created many restore points, although none appear to function. How do I resolve this problem?
A. First, run SRDiag.exe found in Windows XP Service Pack 1 to capture the System Restore change, restore logs, and create a .cab file. This is a precautionary step, and you can e-mail the logs in a .cab file to a monitored alias to Microsoft for troubleshooting if one of the suggestions listed below does not resolve the issue.
Possible causes for restore point failures:
• Corrupt restore point. Inconsistencies between file entries in the System Restore file change log and files backed up or tracked by System Restore can occur, most often from an improper shutdown or power outage while System Restore was adding a log entry during change tracking. Similarly, an entry for the file exists in the change log but the file itself may be corrupt or missing. This can also occur when System Restore pre-change file copies are deleted from the system volume information directory to clean the system. By design, System Restore prevents a successful restore to an inconsistent point — it will fail and then revert to a previous restore with unsynchronized file copies and log entries. To remove corrupt restore points, disable and re-enable System Restore.
• Low free disk space on a System Restore monitored partition. Every restore process involves System Restore creating a restore point prior to the restore operation so that the user can undo the restore process. If you are experiencing failed restores, ensure that there is sufficient free disk space available on all the System Restore monitored partitions.
• Changes occurred to System Restore monitored files on one operating system through another operating system (OS) on another partition or removable drive. System Restore can only restore changes for the instance of the operating system it was originally associated. Therefore, restoring changes made by another OS or alternative partition is not supported, as those changes are not tracked. Resulting restore will fail as log entries and files on the current state will be out of synchronization.
• A required service is not running. Restoring requires System Restore, Windows Management Instrumentation (WMI), and task scheduler to be running concurrently. For step-by-step instructions to verify that these services are active, click on each service or scheduler link.
• During the restore process, files to be replaced, moved, or deleted by System Restore were locked by the system or an application is causing the restore to fail. Please refer to Windows XP Service Pack 1 for more information.
• Behavior between anti-virus software and System Restore. Interaction between System Restore and anti-virus utilities can affect restoration to a previous point containing infected files. For example, if a file used for restoration is infected and cannot be cleaned by the anti-virus utility, System Restore will not recover the computer to a partial or compromised state. How your anti-virus utility is configured, the point selected to restore to, and action taken by the utility on a restored infected file (for example, whether the anti-virus utility successfully cleans, deletes, or quarantines a file), also affects restoration results.
http://www.microsoft.com/technet/community/en-us/management/sysrestore_faq.mspx#EUHAC