If InDesign crashes, it does attempt to recover the work you did, but it uses Recovery Data files in your preferences folder.

When you close the file, the lock file goes away. The solution: Create a little file that alerts InDesign that the file is open and others shouldn’t change it. Adobe realized that this could cause some, um, challenges, especially if two people were trying to make changes to the same file. Why would such a thing be necessary? Because InDesign files are actually databases of information, and like other databases, more than one user can open them at the same time. When I asked an Adobe engineer about it, he told me that the IDLK file is used simply as a marker to indicate that the file is open. Nothign is stored in there (at least nothing that I know of). However, if you check, you’ll probably find that this file is always zero K large. After all, some programs do store recovery data in temporary files such as this, in case you crash. When I started using InDesign, I tried everything to open this file, assuming that there must be some kind of magic in there. Whenever you open an InDesign file, the program creates a “lock” file - with an “.idlk” file name extension - in the same folder. This is a great idea for one of our podcast’s obscure feature of the weeek-eek-eek, but I’m just going to dive in and answer it here for all our readers.

I cant open gmod file locked