When you restart after a crash ID uses the recovery data to attempt to rebuild all the files that were open when the program crashed, but it will do this as untitled copies for safety.
You can open the last saved version of any file that was open most times, too, unless the crash occured during a write operation and damaged the file. My tendency is to do a save as to a new name on the recovered files and not overwtite the originals, just in case, but that can be problematic if you have inter-file cross-references. You should be able to either make a new book file, or replace individual documents in the existing book with the new versions.
So I called tech support earlier today and was guided thru process to remove lots of preference files. I then relaunched ID, created "save as" new files for the .indb book and individual .indd chapter files. I then started to edit the hyperlinks and developed a problem where the program thinks a dialog box is open, but for the life of me, I do not find the open window. I have to force quit the program as it will not respond any other way.
In an attempt to follow up, I phoned and requested a call back. After over 35 minutes on hold from that call back to connect to a person, I hung up. How do I solve this problem? Are hyperlinks a giant problem in ID?