Missing file problem

I have a project which asks for a file *. wav. It looks like the name was accidentally removed, so it can never be found. I don’t notice anything needed missing from the project, which is a song, I’ve built over 20 years and now just improved the drum part by recording with the Roland VAD. So it has never been a problem ignoring the file , closing that window and continue to work on the song. But for the first time, after remote support and chat, I started having problems where after closing that window, I get a spincircle and lockup. I have to use task manager to close. It is uncertain whether I can get back to the song, it seems if manual doc is open, ports selected. I had some better luck opening a version saved before the sessions but even that is intermittent. I feel in great danger of losing years of work becasue of this new problem. I don’t see anywhere in the project where the missing file would be liek an empty box or something and I know I have other projects that give missing file messages that have always easily been ignored. In this case, the file I think has been misnamed with a blank so can never be found. In other cases, probably a move left on drives somewhere. I’m not searching for the files. I just want such messages to end, so where in a project is there a list of files used or something where I can remove those that aren’t in the pool or whatever.