I posted this in the forum where I got the map but thought I might have better luck with a response in this thread. Thanks for any help!!!

Hi all, fairly new to the site but wondering if anyone would be able to assist. I just got a Garmin nuvi 255 and love it, it is a North American unit with CN North America NT 2010.10 loaded on the device.

I was interested in getting this map pack (The Garmin Asia Pacific 2009 (APAC Region), img file), I downloaded it successfully and planned to put it on a micro SD card that I have. On the micro SD I created a folder called Garmin and placed the downloaded file in this folder and renamed it to gmapsupp.img

When I put the micro SD card into my GPS and switch it on, it definitely detects the extra maps as it says "loading maps" and scrolls across on a status type bar. However after that it sits on the "Garmin" logo screen with the copywrite information at the bottom and does not proceed past that. As soon as I remove the micro SD card and reboot the GPS unit it loads as normal but of course only has the devices North American maps.

Hopefully this makes sense and I welcome any assistance, thanks!