Does Backup resolve Corrupt Project?

Got the dreaded “the project could not be saved because the project is corrupt” thingy. I can’t save it but i can back up the project and it opens and plays fine.

Does anyone kow if the Backup function would resolve this or am I going to have to start over again? Is this plugin related ? (Not had this for years - but recently i needed to use Waves Soundshifter and am wondering if its that

Is there a way yet to save the entire mixer and all its settings in 7.5 so i don’t have to sift through every single chain?

many thanks,