How to resolve missing files?

You are going to have to get access to the computer that the files were on earlier.
If they are networked, point to the correct drive/folder/audio and let it find the files.
Then use “Prepare archive” to copy the files to your present working folder. If you cannot
network the computers, you will need to get a copy of the data from the other computer
on some form of portable media and load it onto your system, and then use “prepare archive”.

best of luck,
Brain