We found a problem in '(C) test.xlsx'. Do you want to try to recover as much as we can?

[Formula11]

I've had issues with workbooks becoming corrupt for a long time and couldn't figure out why.
Finally noticed it was when I was copying in a worksheet from another workbook.
The file name is "[C] test.xlsx", the error message shows "(C) test.xlsx" as well for some reason.

Is it because there is a prefix before the file name which is causing the issue?

File

Error message

Repairs