Unable to open up Word doc’s over the WAN

I have a client who can open a word doc fine while on our WAN or ones that are stored locally. However when he visits to any other of our locations and tries to open those same documents over the WAN on our shares, Word opens and just is an empty shell. No error. Doesn’t appear to be hanging because you can close it fine. If you file/open while in Word and goes to those same doc’s they open fine. Also, and not sure if related, he also cannot do a windows file search. it comes up empty even when we know there is such files ie:*.doc, *.pdf etc… AGain, only when working across the wan.