Pack into .Blend (Missing file nightmare!)

Hello, I’m having a bit of trouble packing my .blend file to export.

You see, during the games development the blend file was sent between me and my tutor a bunch of times, now that it’s finished and I want to export it, It confronts me with what seems like an endless mess of missing file errors.

Is there any way of solving this without endlessly trying to relocate each pointless individual file?
The game runs fine in Blender, so all the files must be working, right? I recall trying to fix this a while back but it just wouldn’t stop listing a new error every time one was solved. Every image.001 (.009 etc) created through the .blend files transference is suddenly raising this unfortunate issue which I can’t seem to get round.

Any ideas?