Quick research indicates this error is caused by a failure to find files, which might be because of an error communicating with the hard drive, or missing files. Given the known history, it seems likely that the issue is just that some files cannot be read.
This probably means that your filesystem volume (a.k.a. partition, C:) is corrupt. I'm sorry to be the bearer of bad news (and I recall people downvoting me the last time I did this), but that is my honest opinion of the current situation.
Before making any further changes, back up what you can. If there are important files that are not backed up, try to copy them (or recover them using something like TestDisk). A safer/wiser/harder/more-time-consuming approach is to create an image of the entire hard drive, which can then be useful for being able to make multiple safer rescue attempts of any desired data.
At this point, I would not trust the filesystem volume for storing data until the filesystem volume has been successfully repaired by repair software like chkdsk. Such repair might not be accomplishable, and so your only recourse may be to re-create the filesystem volume, which will delete all data. However, once that is done, the new filesystem volume would then be expected to be reasonably reliable (as long as there are no hardware issues).
If you can get a filesystem volume repair program (like Chkdsk) does say that the filesystem volume is okay, that probably means that free space is trustworthy, and that some (and possibly all, but not necessarily all) pre-existing data is not corrupted. If the data is really important and you're seriously concerned about its integrity, you may need to restore from backup or re-install/re-create data.
Until you get the filesystem volume repair program, there is a very high chance that an operating system will see some file entries, so it will look like the files exist. Interacting with some files might even be possible, and so you may be able to copy the files. However, interacting with (some) other files may not be possible. (Attempting to read the bits belonging to the file may cause an issue, as some of the bits may not be properly locate-able.) Also, the system's records of available free space may not be reliable, so writing to free space is not recommended. (Doing so might cause further corruption of some data that would otherwise by retrievable.) Even if quite a bit of data seems okay, I just wouldn't trust the filesystem volume until a completed process of repairing or re-creating the filesystem volume.