Okay, here is something to try…
Take a broken project and copy it to a new folder and then rename it ‘[project].zip’ or ‘broken.zip’. You may need to check your windows settings in order to make sure the extension of the files is also changed (or you can use the command “ren project.scriv project.zip” from the command prompt).
Now, unzip broken.zip. You will see a folder named the [project].scriv where [project] is the original name of your project.
Inside that folder you will find [project].scrivx and more folders.
At this point, rename [project].scrivx to ‘[project].old’ or simply delete it (you are working from a copy right?)
Next go into the ‘Mobile’ folder and copy from that folder ‘binder.mob’ into the higher directory and then rename ‘binder.mob’ to ‘[project].scrivx’. Remember to sub in here the name of your project.
Zip up the [project].scriv folder, then rename the archive to “[project].scriv” and try to open it with Scrivener. It will throw up some sync errors, but show resolve the sync issues and may leave you with a working project.
I highly recommend that if this does work, you “SAVE AS” and start working on the newer copy.
You can look here to see how I did it several years ago. If you do look there, I was using the Mac version of Scrivener, and so things look a little different, but “show package” in Mac is the same for you as renaming the project to a .zip file and unzipping it, with more steps.