System State backup and System Reserved partition exceptions

We have a device running Windows Server 2008 R2 for which we cannot get a good system state backup. That backup consistently completes with exceptions regarding locks on some .DAT files under the 100 MB System Reserved partition (based on the problematic GUID reported in the avtar log). Here's the log snippet showing the source of the exceptions:

2014-09-22 04:14:09 avtar Warning <7312>: Cannot get Security Descriptor for file "\\?\volume{1dce34a8-82f3-11e1-ae37-806e6f6e6963}\System Volume Information\2331{3808876b-c176-4e48-b7ae-04046e6cc752}". Error=5 (code 5: Access is denied)

2014-09-22 04:14:09 avtar Error <5139>: File access share error "\\?\volume{1dce34a8-82f3-11e1-ae37-806e6f6e6963}\System Volume Information\001.dat" (code 32: The process cannot access the file because it is being used by another process).
2014-09-22 04:14:09 avtar Error <5139>: File access share error "\\?\volume{1dce34a8-82f3-11e1-ae37-806e6f6e6963}\System Volume Information\002.dat" (code 32: The process cannot access the file because it is being used by another process).

This exception causes the entire system state backup to fail in that there are no available system state restore points for the server (the job status is still Completed w/exceptions. Any advice on common causes and fixes?