Accidently Deleted the Garmin 100K Topo - what are my options?

Started by staggart, July 13, 2015, 12:50:37 PM

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I recently purchased an etrex 20 with the garmin 100k topo installed on the SD card.  I had copied other maps from gpsfiledepot to the sd card and accidentally deleted the garmin topo 100 .img file when cleaning up the other topo files.  I happened to have copied the garmin .img and other files from the SD card to my PC in case I did something like this.  Thinking I could just copy the files back to the SD card from my PC and be in my way, I was in for a rude surprise (unit says it cannot unlock map).  I called garmin and they told me to insert $100 for a new map.  Are there any options?  I tried to convert the .img file using the MapSetToolkit but that crashes (because I have no .TYP file so I made up an empty TXT file?).  Thoughts?  Related to this - I searched this site for a US topo but can only find individual states - is there a single US topo file posted somewhere?  Thanks in advance.


It would be against the policy of this site to discuss any methods of unlocking/converting a commercial map from Garmin.

However, I'm surprised that you could not copy your backup to the card and get it to work. This kind of map is locked to the hardware ID number of the original card. I have always read that you can backup these maps to your computer and restore them in the event of a problem. Are you certain that you are copying all the original files to their original location on the card? You must use the same card the map was originally supplied on. I believe there will be three files: the .img file is the map itself and there would probably be two files used for copy protection, one with a .gma extension and possibly another with an .unl extension.

Aside from that, I think you're out of luck unfortunately. :(

It doesn't make much sense to purchase the Garmin topo maps on SD cards IMO. The DVD version is not locked and can be installed on any Garmin devices that you own, so a backup can be restored to any card. The download version will be locked to the original GPS, but it can be backed up and restored to any card. Garmin also allows you to download the map again at any time for 12 months.

Almost all maps on this site were created at 24k resolution. Not sure if it would be possible to fit the entire US into a single 24k topo map and stay within Garmin's spec. Garmin maps can only have a total of about 4000 segments - the smaller tiles that make up the whole map. If you purchase Garmin's own 24k maps, I know that you can't even come close to fitting the whole US before this limit is reached.


yeah, I get that there are copy protection issues here...

I purchased the SD card as part of a bundle, so the DVD was not an option in this case.

Yes, I have all three files - the .img, the .unl and the .gma files and I copied them into the same place they were before on the same unit.  Garmin told me "when you delete the files from the unit, the unit will no longer recognize those files".  Not 100% sure the garmin person understood that I was coping the same files back.  Perhaps the files are "location" based  on the SD card somehow (maybe the lock file knows the disk sectors where the originals were stored or something goofy like that).

I thought it was worth asking since I did pay the maps when I bought the unit.


What is the name of the file you copied off the sd card?
Dan Blomberg
Administrator - GPSFileDepot
GPS Units: Garmin Dakota 20, Garmin GPSMap 60csx, Nuvi 255W, Nuvi 250W, ForeRunner 110, Fenix 2, Tactix Bravo, Foretrex 401
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gmapsupp.img - 3,284,288 KB
Gmapsupp.unl - 1 KB
grmn0.gma - 3 KB




All 3 files should be stored in a folder with a name: Garmin