The name is TimeLog.xls . I have been using this file for months and accessing it via the Recent Items list (until today). I renamed it to TimeLogRH.xls and it is appearing in Recent Items with no problem.
I occasionally have a similar problem with several very long MS Word files that I use daily for months or even years at a time. Sometimes, something gets corrupted when I am constantly activating the files and changing data.
It sounds like, since you have already renamed your file, the simplest thing for you to do is to delete all copies of the original file, and then, hopefully, you can rename the new file back to its original name. I would do an Advanced Search (of the entire system) for all files with the original name, specifically making sure that your search includes the "real" file located at
C:\Users\[NAME OF USER]\Documents\[NAME OF FILE], as well as any copy that might be in a Temp folder, Recycle Bin, or anywhere else on your system. Then, shut down and reboot. Hopefully, since all remnants of the original file will now be gone, the system should let you rename the new file to your original file name, and, because it is technically a
new file, it should show up in your recent files list.
For the future, just as a suggestion, I ALWAYS make (and keep updating) a 2nd copy of each of these long files, so that when the original gets corrupted (which it usually eventually does), I at least, have the up-to-date copy as a backup. And when that happens, the first thing I usually do is transfer a copy of the
backup file to a memory stick, just to be twice as safe.