Failed to Create Empty Document Arcpad 7.0.1

[BruceSchaepe]

We have Arcpad 7.0.1 installed on an older Mobile Mapper CE with Windows CE >NET version 4.20.

Arcpad was working OK until recently.  Now, when we start the program we get several errors beginning with:

This an an unregistered ArcPad installation. ...

Failed to create empty document.

Fatal application error.  Application ArcPad.exe has performed an illegal operation and will be shut down.  If the problem persists, contact the program vendor.

Program: ArcPad.exe
Exception: 0xC0000005
Address:  001CD7B4

[RickKoehler]

We just had one of our users report the same problem with ArcPad 7.1.1. We have about 40+ installations, and when I installed ArcPad 7.1.1 on this users new PC, everything went fine, but now he is getting the "unregistered copy" message.
And, when he enters the correct serial number/registration code, it still says he has a unregistered version that will only work in demo mode. As he is in a remote location, I can't verify that he is entering the correct one, but when I had him read it off to me, it was correct.

The serial nmubers we have still work, as I re-installed for another user (who also received a new laptop) after I worked on the case above, and everything was fine (using another serial number of the same vintage, that was assigned that second user).

Plus, I must note the lack of official ESRI response to this thread, after almost 4 months.
???