Acrobat 11 on Vista won’t update from 11.0.8 to 11.0.15 saying "No update needed."

Using "Help>Check for Updates" I updated our installation of Acrobat 11 on Win 7 from 11.0.8 to 11.0.15 no problem.

But when I "Check for Updates" on Win Vista SP2, it says No updates are needed. I can't seem to get it to recognize that it needs to be updated. I want to

I want to install the security update announced by Adobe for Acrobat in APSB16-14: https://helpx.adobe.com/security/products/acrobat/apsb16-14.html.

Does anybody have any ideas on how to get Acrobat to recognize it needs updating?

Thanks,

Jay