The Save As dialog box in Acrobat DC doesn't allow you to save any files; it's blank.
Possible reason: The Save As dialog box in Acrobat DC has an additional option to save files in the cloud. If Acrobat can't connect to the cloud, the Save As dialog may not work correctly.
Caution:
If you turn off the online storage options, you won't see the cloud options for opening or saving files in Acrobat DC.
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