I tried to speed up the missing file detection by first building a dictionary of the paths of every file found in the storage location (and all subdirectories). I then iterate over every song in the library to see if the paths of the files in use by that song are found in that dictionary. I'm not sure why this approach is generating the unusual errors you are seeing. I can go back to the old approach where I just look at each file and check to see if it exists. I just tested this with a library containing around 5500 songs, and the old approach is actually faster (there wasn't a noticeable difference with only about 500 songs). I'll push another update at the end of the week to address this and any other reported bugs.
"Find Missing Files" is working again in 1.9.9 - thank you Mike.
But some new issues are to be reported:
1. there's no "Fix Broken File Paths" option in the Win10 version as it exists on Android
I'm not sure if I ever used it before on Win10, it would be useful anyway
On the results page of "Find Missing Files" I clicked on one of the missing files and selected a new PDF in a subdirectory of the MSP folder. "Swap Files" opens
2. There's no "Use from the selected path" option. The path of the selected file is fine, I do not want to move or copy it. The handling on Android is completely different, no "Swap Files" window, just selecting the new file.
Maybe "Use from the selected path" has to be greyed for paths outside the MSP folder as that's not possible on Win10.
3. NullReferenceException: I select "Copy new file to same folder as replaced file" - just to see what happens, the original folder /storage/sdcard0 is a remainder from Android (which is definitely strange on Win10). That leads to a NullReferenceException. Not a big problem, "OK" closes the message window and I'm back again without further issues.
4. I select "Copy to MobileSheets folder" instead. "Copied successfully" is reported, the file is copied correctly. But it stays in the list of missing files with the unchanged old path. When I click it again "unknown error" is reported. Restarting MSP as proposed by the error message is not required. "OK" closes the error window and I'm back again. I can close the missing file list and MSP works as usual
