Hopefully there is someone who can help me ASAP. I have not been able to Save as, Save a Copy, Place and Export in InDesign for a long time. This applies to all my documents. I have so far been able to fix the problem by uninstalling InDesign and then reinstalling it again, but now this is no longer possible ...
Import and export
Try resetting your preferences: The easiest way to reset everything is to delete the InDesign preferences: as soon as InDesign starts to boot hold down Shift, Alt, Ctrl (and Apple/Cmd if working on a Macintosh). A dialog will appear asking to delete the InDesign Preferences, select 'Yes' on this dialog. Further info and instructions here if needed: https://helpx.adobe.com/in/indesign/kb/indesign-preferences-support-file-locations.html