Thank you for your post.
When you launch FileMaker Pro, it looks across the network to see if the same License Key is being used elsewhere on the network. If it finds a copy, then you will get the error message that too many licenses being used.
Make sure your office computer is not running FileMaker Pro when you try to access from the outside. Then, you will be able to access the database file from outside your office.
Yeah, well, my office computer is hosting. My only option would be do install one of the other 2 licenses and only use them when the staff is not in the office, or pop for another $400 for a 4th license. Which isn't really an option right now. I just paid for 3 of them.
I guess I could always try Screen Sharing. It's harder to see, but it would work for the time being. It's a shame, because the two installs was a definite plus for me.
use Remote Desktop to your office computer.