It's very rare for a file to become corrupted. The most common way it happens is when something goes wrong while a file is being
saved. For example, the program saving the file might crash, or our computer might lose power just as the file is being saved.
Based on your description, I think the files getting corrupted may be caused by the unexpected shutdown of the server. We may try
opening Event Viewer to see whether some events have been logged there.
To start Event Viewer, the following article may be referred to for some help.
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