Attach to email button suddenly not reacting in Acrobat X but works in Reader

I have a user here who can no  longer use the "Attach to email" function in Acrobat X. I am working for the same company so I tested my Acrobat and it works just fine. All our computers are set up the same way. She had no recent installations that could have interfered with the button. I downloaded Reader for her and it works there just fine and opens with her default email handler, Outlook.

In Acrobat I am unable to check the Internet settings for this as the option to "Set program access and computer defaults" is set by our Group Policy and even with my admin password am unable to access it. Since it is working in Reader I presume that Outlook is the default email handler. Especially since she had no issues before, it just suddenly stopped working.

The most significant difference I noticed is that I have a "share" tool next to TOOLS and COMMENTS in Acrobat but hers is missing.

I tried to open Adobe with the Shift button pressed but I will get a "Program stopped working" error and then it closes.

I repaired Acrobat as well to no avail. Does anyone have a clue what's going on here? I googled the subject but most people get an error message, which she doesn't - it just doesn't do anything. Also, I couldn't find anything regarding the missing Share button.