If you receive the following error in your backup log, when the log is viewed from the Logs tab via Log Viewer app (LogViewer.exe):
Error: An unknown error occurred during backup processing.: FileSystemException
How to Confirm
You will need to view the verbose error for "FileSystemException" which you can do if you view the .xml file in a web browser or plaintext editor such as Notepad. On the backup client machine, navigate to the Logs folder used by the backup client (by default
"C:\ProgramData\NovaStor\NovaStor NovaBACKUP\Logs") using Windows Explorer.
Locate the time and date that the backup job in question was created, there will be two log files generated for one backup job, one will have
"xx.files.xml" for the filename and the other will have
"xx.summary.xml" for the filename. If you were to open the same log file (.XML format) with a web browser (ex Microsoft Edge, Google Chrome, Firefox), once open search for "FileSystemException" to find the following verbose description for the error and see if it looks like our example of this issue:
<message>Cannot create directory 'C:\ProgramData\NovaStor\NovaStor NovaBACKUP\xSP device.0\Backup\.\SERVER\C'</message>
<exception xml:space="preserve">exception FileSystemException : Cannot create directory 'C:\ProgramData\NovaStor\NovaStor NovaBACKUP\xSP device.0\Backup\.\SERVER\C'
checkpointed at BackupSvc.cpp (1362)
thrown from FileSystem\Directories.cpp (307)
caused by exception Win32ErrorCode : Function: CreateDirectory, error = 0x8007007B, The filename, directory name, or volume label syntax is incorrect. thrown from FileSystem\Directories.cpp (283)
If the error in your case is shown as
0x8007007B, like our example shows, then it could be due to a registry key setting that needs to be corrected, if the backup client computer is in a Workgroup. It could also be that the machine was in a Workgroup at one time and that registry setting was leftover, after joining to a domain.
That error when the
xx.summary.xml file is viewed in a web browser will look like this:
Analysis of the error
Here it mentions
"Cannot create directory 'C:\ProgramData\NovaStor\NovaStor NovaBACKUP\xSP device.0\Backup\.\SERVER\C\_Temp_'". This means that the xSP Backup Server was not able to get to the backup client computer, in this case named "SERVER", the SERVER (running the backup client) computer is not on the domain but is in a Workgroup, called
"WORKGROUP", to then be able to write files to the
C:\Temp folder. Here we can see that the computer with the backup client installed on it is in WORKGROUP:
The issue we are detailing here does not actually have to do with permissions not being set properly in this case, although permissions is normally an issue, most likely in this scenario it is just having issue with a single registry key that now needs to be verified and then set properly for the backup client to gain access to its own folder. Note: We have seen that even though NovaBACKUP xSP may have been able to complete backups in the past without this error it may require the registry entry to be set properly now.
What you need to do on the backup client computer, is to load Windows Registry Editor (regedit.exe) as a user with Administrator rights, and locate the following registry key:
Verify what is displayed as the value data for the
DefaultDomainName registry key.
If the value data is
. you will need to modify that key and set the value data to either be blank or you can set it to Workgroup. In our case the value of DefaultDomainName was
., which caused the issue, and needed to be changed to
blank. If the registry key does not exist at all at this location, then you will need to create a new string value key named
DefaultDomainName, by right-clicking in the empty space in the Winlogon area, and choose
String Value and name it
DefaultDomainName, for the Value Data you can leave it as blank or set it to
The registry setting should then look like this:
After setting the value data to blank in this case, it is required to restart the backup client service (nsService.exe) and the backup client (the NovaBackX.exe task).
To manually stop NovaBACKUP Services:
- Press [Ctrl], [SHIFT], and [ESC] keys simultaneously to open the Task Manager window.
Select More details at the bottom of the window.
Select Show Processes from all users at the bottom of window.
- Open the Details/Processes tab
drdiag.exeprocesses are not active.
- Select each of them and choose [End Process] or [End Task] if they are still active.
- Opening NovaBACKUP will restart these services automatically
You can then try running the same backup job that failed with the "FileSystemException" error again to see if it can get beyond that issue and start writing data to the Temp folder. Verify the backup log again in both Log Viewer and using the web browser method to confirm the error is no longer being generated.
What you need to do is change the registry key:
From ‘.' To either blank or 'Workgroup' for the value data.
If you still have this issue after restarting the backup server and backup client computers, and verifying the registry key is set properly, and running the same backup job still fails with the same "FileSystemException" error, please create a support ticket at novastor.com/ticket. You can tell us that you followed the steps in this article and it still is not working for you.