I'm stumped...

I have five computers running Acrobat Reader, all used to open the same file. On four of the computers, the .pdf opens to full page like this, which it is supposed to do:

One of the computers opens the file looking like this:

I have compared the settings on all of the computers and they are the same. 

I'm stumped. What would cause one of the computers to open the .pdf file differently from the others?

Thank you.