First of all, make a backup copy of this folder, just in case.
Then check if there are any files ending with ".backup" or ".autosave"
If you find such file, rename it (remove ".backup") and try to open.
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Also, check this folder: C:\Users\YourName\Local Settings\Temp
Sort by new, see if there are any recent folders with names like "CAP123456". Copy them to a safe place and check if any of them contain your project.