Before I installed Win 10, I had a large number of photos on my D drive. After installing Win 10, D is now called Recovery Image -- and my photos were moved. This seems to involve 500 to 1,000 files. So far, I have not found a pattern for where the files were placed. (Prior to installing Win 10, I had pictures stored on C.)
I thought about using the Import function, but I might lose my tags. When I reconnect a single photo, I check the box to reconnect other nearby photos, This seems to only pick up a few additional items. Does anyone have a solution?
Sounds like the Windows installer may have changed drive letters on you. Use Explorer to confirm what your current drive letters are.
Assuming it is just a drive letter problem, in LR go to the Library module, Folders panel.
Right-click on one of the top-most folders that is marked as missing "?", select "find missing" or "relocate" or something to that effect, navigate to the current location of that folder. Repeat for all your top-most missing folders. LR will update everything under each folder automatically.