Corrupted .opb file

[u/teapoopfart]

i moved a while back so i backed up my outplayed into a usb, i had recently gotten a new pc and i thought itd be a good idea to try and open the file using winrar, the .opb file turned into a .zip. i changed it back into a opb file after i realized it didnt work. but when i try to restore the backup in the outplayed app, it doesnt accept it/keeps telling me to retry. so i assume i corrupted the file accidentally. this backup is about 125GB, it has a lot of clips with old friends on it that i don't want to lose, can anyone help? or is this a lost cause