My first thought would be that the GPS receiver itself is just fine. In the past I used GM-210 by Holux, too. For over two years it was sitting on the roof exposed to extreme summer and winter temperatures, rain, snow, etc. The receiver has an internal rechargeable battery which will get discharged if not used for several weeks. When first used after a prolonged period of not using the receiver it may take up to a half an hour for your GM-210 to get a satellite fix. Just keep it plugged in to your computer and let the GPS receiver have a good view of the sky for 30 minutes. After that it should by okay again.