When a backup completes, you may encounter a Windows event log similar to the following:
Volume shadow copy service error: Unexpected error on routine call
IVssAsrWriterBackup::GetAsrMetadata. hr = 0x80070001, Incorrect function.
The issue (event ID 8193) may be caused by an invalid entry inside the following registry subtree:
- Open the Registry Editor (regedit).
- Expand into the abovementioned subtree and check within it if there is an entry that has a .bak value appended. If so, this may be causing the failure when trying to resolve the SID of the writer.
- Backup the registry key first, then delete the entry with the extra .bak value.
- Reboot the machine to check if the issue has been fixed.