Hello there,
Yes, you can run VSS when your system is idle. However, I have found the below points that might be helpful for you.
Backing up and restoring critical business data can be very complex due to the following issues:
The data usually needs to be backed up while the applications that produce the data are still running. This means that some of the data files might be open or they might be in an inconsistent state.
If the data set is large, it can be difficult to back up all of it at one time.
Volume Shadow Copy Service https://learn.microsoft.com/en-us/windows-server/storage/file-server/volume-shadow-copy-service
Hope this resolves your Query !!
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