Can't "Save as" on Acrobat X

[chipdemetri]

After I optimize a multi-page PDF by deleting duplicate copies of fonts, I am unable to do a "save as" and overwrite the original file.  It either does nothing, or i get a message saying the file is either "read only" or currently in use by someone else.

I am using Acrobat 10.1.16

I am on a Macintosh using El Capitan 10.11.4 (2.8 ghz Core i7)

Thank you,

Chip

[maxwyss]

If you hand't specified you were on OSX 10.11, I would have said you see an effect on Windows, where the preview function in the Windows File Explorer grabs the full access rights to the PDF.

Could you check whether that file is somehow opened elsewhere (for example in Preview, or the Finder).

[chipdemetri]

Thank you for the reply.  The file isn't opened elsewhere.

Interestingly, it works the first time I do a "save as".  Every time after the first time, it doesn't work.  It either does nothing or gives me the message that it is "read only" or in use by another person. 

Thoughts?

Thank you.

Chip