Recent upgrade of InDesign and Illustrator interchangeably sometimes loose file integrity, and new projects cannot open or must be imported.
File locations get lost or the "version" of the InDesign or Illustrator that the file was created in is no longer available. Didn't have these issues before the last CC upgrade. Just yesterday, I saved an Illustrator file and know that I saved it. Then, did a save as to rename and make changes for a new version. The previous version vanished, an image in the recent listing menu appeared, but couldn't be found to open. Now vanished as if it never existed. Had to start my original file over using my now changed version. Just took the entire morning doing it again.
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