No valid GPS signal....With a twist

Hi everybody. I'm new to the site and have been directed here by somebody that this site helped in the past. I'm hoping you can do the same for me.

I have an ipaq 2750 with windows 2003 and TomTom 5 that I run with a"G-Mouse" GPS receiver which is a CF card type receiver. I've read through many of the threads on this same subject but they all seem be be different from my problem in the fact that my navigator and receiver have been working fine for nearly a year now. The problem started when I went to France in August. I took my PDA, switched it on in the South of France and immediately started getting the "No valid signal" message. It has not started working even though I have returned to blighty. So far I have...
Reinstalled all software
changed location within the GPS receiver software
set up "other NMEA device" (or whatever it says)
Baud rate 4800 (it wont work at all at 9600 or above)
CF CARD GE is all set
Com port 1

and everything else I can think of. The lights on my receiver flas as they always have. The blue and yellow disc spins as it always has. It even switches between "No GPS device fitted" to "No valid GPS signal" and "awaiting valid GPS signal" and "GPS signal lost 25...30....35 seconds ago" etc. so it indicates all is OK, but when you go to the sattelite information, it doesn't even show any of the bars turning grey let alone blue thus indicating it is not locking on to even a single sattelite. I've left it with a good view to clear skies for hours and still nothing. The strangest thing as already mentioned is that it has been working fine for nearly a year....al until I went to France and now nothing !!

All help greatly appreciated as this is driving me nuts
Thanks in advance.

Graham