I have a Garmin Nuvi 205W problem?

I have a Garmin Nuvi 205W which is about 5 years old. A few days ago I tried to update its maps (I have a lifetime subscription) and a message came up after about 20 minutes to say the process was complete, so I unplugged the device. Now when I try toi turn it on I get an error message "System Software Missing" and the device won't work. Plugging it into the computer doesn't help as the Garmin updater can't find it (although the computer "chimes" to show it's found the device).

I wrote to Garmin customer relations and got a very offhand answer that basically said, "We don't support this model any more, so tough doodies".

So I went onto the Garmin service site and found my model and clicked on the "repair quote" request box - to get the answer, "This model is no longer repaired".

I accept that 5 years is a long time in computer terms - but the device does everything I want and I don't see why I should have to lash out over £100 to replace it when all that's wromg is some minor software glitch.

Any ideas as to how I can fix the SatNav or get someone in Garmin to behave as if customer service weren't an unknown concept