Thanks.

I think the Garmin Asian software delivery is quite inconsistent. According to both Garmin US and Garmin CN websites the latest for nuviC255 China is V2.80 yet your friend's has V3 loaded, no wonder it didn't update:
Code:
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However, other sources indicate that there are later versions for other regional models of nuvi devices HWID 1958, e.g. India is V3.00; Thai and SG/MY is V3.10 and Indonesia and Philippines is V3.20, so go figure.

After what you went thru with your devices, I think you were very wise to just load a usable kb to your friend's C255 and give it back. 'Discretion is the better part of valor' .