Suddenly I can no longer open two indesign documents. The error message is shown in the picture. I've done all the updates but it didn't help. Does anyone know how I can get the files open again and edit them? I do have a PDF document of the file.
That looks like an icloud backup file of some sort and InDesign doesn't know how to deal with it. Note that the filename ends in .icloud rather than .indd
Maybr a lock file was not deleted when it was finished the last time. Delete it manually. Those lock files are beside the original file and hinder others to open the same file at the same time.