Where do I start? I'm a complete newbie for Garmins. I have been updating Tom Tom's for many years. Have just been asked to update my step-daughters nuvi 30. Tried looking at the tutorials but a lot of the links no longer exist. Sorry for being a pain, but just don't know where to start. Thanks in advance for any help.

If it's a Nuvi 30LM (LM = free lifetime map updates) you can go to the garmin site and use their tools do your free updates.

If it's a straight Nuvi 30 you don't get free map updates from garmin. The 30 has limited internal memory and it can be a pain making things fit. I'd suggest you leave the GPS alone and get a cheap 4gig micro SD and just put any future updates on SD as an additional map. The SD will solve the space problem and allow you to use full maps.

Unfortunately you haven't mentioned what maps you are trying to replace (USA, CAN, EU, etc).

If you go the SD route it's very simple. You need only 2 files in the proper locations/folders and your done. A card set up like this will work.

sd:\garmin\gmapsupp.img <--- gmapsupp.img is an UNLOCKED IMG file (your complete map)
sd:\garmin\JCV\DxxxxxA.JCV <---- the junction view photo file. The name matters as it is specific to the map you are trying to use.

You can also set the card up this way
sd:\Map\gmapsupp.img <--- gmapsupp.img is an UNLOCKED IMG file (Map folder name is case sensitive)
sd:\garmin\JCV\DxxxxxA.JCV <---- the junction view photo file. The name matters as it is specific to the map you are trying to use.

Apologies, forgot to mention it's the UK & NI map. I have downloaded a new unlocked image and associated JCV file. When the Garmin comes back from it's Scotland holiday will try your suggestion. Thanks for your reply