Recent files are grayed out and not available to be attached in mail programs or selected for all programs by file chooser.

Ok - the title shares half of the issue because the file is actually available once I click out of the enclosing folder and then back in. Common scenario. I attached a pdf to mail and relize I have an error in the pdf...back to Indesign to fix the issue- export to pdf - return to mail - click attach (default to same folder as chosen before) - the file is present but grayed out. If I go out of folder and return...it is now available. This happens in every app I use and multiple mail docs and programs. Adobe/Microsoft etc. This is a file chooser issue and possibly a Dropbox Issue but cannot solve.