[AccessD] Dreaded "Function Name That Microsoft Access Can't Find"

I get this message when I simply call a basic function from within Access
'using a macro'.

But I can call it from the Immediate window.

The user was half way re-loading WIN XP on his PC when he cancelled the
process. XP was already on it so there was no need for him to run the setup.
Once he realized it he cancelled it. Now Access won't work correctly. Any
ideas?

John Skolits