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I downloaded a central america map and when I try to unzip or open I get Error: Internal error processing iso image. Does anyone know how to fix? Thank you.

asked 25 Apr '11, 20:34

tdfam2's gravatar image

accept rate: 0%

edited 11 Feb '13, 00:35

aseerel4c26's gravatar image

aseerel4c26 ♦


Where did you download the map from, and what exactly was the download link? OSM doesn't make ISO images available, so either you downloaded the file from somewhere else (and would have to ask them why the file is broken), or maybe your system thinks that the file is an ISO image when in fact it isn't. What operating system do you have, and how do you try to "unzip or open"?

(25 Apr '11, 20:41) Frederik Ramm ♦

I downloaded from I have windows xp and when I try to open with win zip I get the error mesage. I attached my garmin nuvi 200 to my computer and drag and dropped the file into a folder on my garmin's sd card but still not getting maps.

(26 Apr '11, 11:43) tdfam2

I've just downloaded the Central America map from there, copied it to a "Garmin" folder on the micro-sd card on my Nuvi 265w, searched for "Belize" (via Where To / Cities / Spell) and got a map of Belize City. The mapping's a bit incomplete, but that's because the data isn't in OSM yet.

(26 Apr '11, 14:48) SomeoneElse ♦


It sounds like you are trying to double-click, or otherwise open, an .img file intended for a Garmin GPS.

You shouldn't do this. Double-clicking tells your computer to "find the program that will understand .img files, and open this with it". But this .img file is not meant for a program on your computer. It's meant for your Garmin GPS unit. Assuming you have an SD card installed in the card socket for your Garmin, simply do this:

  1. Connect your Garmin to your computer via a USB cable.
  2. Put your Garmin in USB Mass Storage mode. (On an eTrex, this is typically done by going to the menu screen, then Setup -> Interface -> USB Mass Storage.)
  3. The Garmin should show up as a removable disc (like a USB stick) in the usual place. On a Mac, for example, this will be on the desktop.
  4. If there isn't a folder on the Garmin called 'Garmin', create one.
  5. Into this folder, copy the .img file that you downloaded.
  6. Rename it to gmapsupp.img if it's not already called that.
  7. Eject the Garmin as you would a USB stick. Again, on a Mac, you do this by dragging it to the trash.

When your Garmin reboots, you should now have the OSM map displayed.

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answered 25 Apr '11, 21:14

Richard's gravatar image

Richard ♦
accept rate: 18%


I registered here just to say thank you Richard, you are awesome.

creating a folder named Garmin into the SD/memory was the solution. then inside it i copied the downloaded maps and it works fine. Thanks again

(28 Feb '13, 12:04) Xchesskiller

Probably a silly question but what if you already have a file called gmapsupp.img in the Garmin directory of the micro-sd card? In my case, this is one of 3 files I purchased for topo Australia/NZ. Sub-directories?

(16 Jan '16, 07:40) Tasilee

What made and model of gps? Leave the name of any purchased maps unchanged. See advice from on "Installing the maps on the GPS"... Most modern units allow a new name for your new .img file but the maps must all be in the Garmin directory.

(16 Jan '16, 10:50) nevw

Thanks nevw. I have an eTrex 30x and from what I can find out online, the .img files can be renamed to anything as long as they have the .img extension. I have a Garmin Australia/NZ topo micro SD that is nearly full so I have ordered a new 32GB card. I have also downloaded an Andes topo so need to wait for the card to arrive before I try renaming the Andes gmapsupp.img and placing it in the Garmin folder.

(16 Jan '16, 22:56) Tasilee

Yes, I would also leave the 'Garmin Australia/NZ topo micro SD' intact and use another card. I have an eTrex 30 and have multiple differently named .img maps, all in the garmin folder on a 𝜇SD, but normally only have 1 or 2 enabled at once. You may find a way to add the garmin topo to the new card if you need to display together with an osm map or just add the osm map to the internal memory of the GPSr into the garmin directory instead of the card.

(17 Jan '16, 02:56) nevw

Thanks nevw. I was unsure how many maps I may want on the 30x so after talking with the Garmin helpline (who were helpful), they said it would support 32GB. Given most of the maps I see are about 2GB, I then at least have the option of having coverage on travels. E.g., I need decent maps for hiking in Germany and Brazil/Argentina on an upcoming trip. I would not expect track logs to take much room, but good to have the larger card so I don't have to worry. I presume I should be able to save the logs to the micro-SD card?

(17 Jan '16, 22:58) Tasilee

The gpx track logs are not able to be saved on the mSD on mine but take very little space. I have mine set up to save a daily archive. Ocassionally I make a backup of both drives onto my computer.

(17 Jan '16, 23:14) nevw

To be more specific, the etrex saves the gpx tracks it creates when you go for a hike to the internal drive. Any tracks you create on a computer prior to your hike to guide you, can be saved to the the gpx folder of either internal or micro drive and work fine either way.

(18 Jan '16, 08:32) nevw

Thanks nevw for the gpx tracks info. Bummer, but as you say, they are smallish files so can stay in main memory. So what happens if you say "Archive". One would hope that they should be able to be stored and read from the SD card. Think of a standard computer that can only read some info on an SD card. People would get pretty mad.

I just got my 32gb micro SD card and did a straight copy of my Garmin Oz/Nz topo 4gb micro SD content to the 32GB card (same folders) and it says it can't unlock the map. Great. Now I have to wonder why I bothered with the larger card if you can't copy purchased maps to it! That is pretty nasty of Garmin, surely!

This needs more homework, and maybe a call to Garmin. One wonder why they even bothered to tell me that the 32GB card would be supported.

(19 Jan '16, 07:32) Tasilee

The garmin maps are protected from copying as expected, though JAVAWA may help to back up to your new card(?)

You should become familiar with - in particular the JaVaWa Device Manager for your gps and JaVaWa GMTK for the maps on your computer as these will sort out many issues you come across from time to time.

You can copy all the archive files to the card and use from there if you wish. On mine I must do this manually.

Your new card hopefully gets some use with the travels you have planned with downloaded OSM maps and you can also use to backup photos. You may end up wanting to put paper maps as customs maps on your gps too

For Garmin issues that are not osm related, I recommend asking the experts in this newsgroup

(19 Jan '16, 10:49) nevw

If I do a straight copy of my two Garmin maps on the new 32GB microSD card, the GPS doesn't recognise them even though BaseCamp does. That I find odd. So I rang Garmin to get the official line on maps and SD cards. They said "Strictly one map/sd card". Ha.

I got the JaVaWa Device Manager and that works dandy. Somehow I got both my Garmin maps onto my new SD card and recognised by my eTrex 30x. I can't however get JaVaWa GMTK to find ANY of my purchased maps on my PC, so I am about to email a query. I have no idea where it looks.

OSM looks good, but as I have the Australia/NZ topo, it seems superfluous for now. I suppose as OSM improves, it will become more attractive.

(20 Jan '16, 20:03) Tasilee

Thank you, Richard. I also registered to say thanks for your help.

(13 Mar '17, 04:03) Sm5555

Thank you Thank you Thank you FULL STOP

(15 Feb '18, 20:38) matthewalexhart
showing 5 of 13 show 8 more comments

You can create a folder in your garmin device, name it "Map" then copy the "gmapsupp.img" file into it then it should auto load after.

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answered 06 Jun '13, 10:02

TheSword's gravatar image

accept rate: 0%


this exact method worked for my garmin nuvi 2797

thank you :)

(06 May '15, 09:30) zaimc

I registred to say thanks... this method worked for me too. nex to GARMIN folder, I created a MAP folder and than copied the image file. everything works just fine.

thnks a lot again. Gabriel

(20 May '15, 20:42) angel_gabe

2015-08-03 This method worked very easily on my Garmin Nuvi 3597LM. As a note, after creating the folder named "Map" and copying the "gmaspupp.img' file into that folder, I ejected the device & booted it. After the splash screen/boot screen, the device popped up a notification that I had an upgraded map. After a accepting, it took me to my map & it showed all the new content.

Thanks for posting this answer!!!

(03 Aug '15, 22:03) Tip DS

Seems to have worked for an install of UK and Ireland Maps on My Garmin Nuvi 3597. It did require creating a Map folder, and renaming the .img file

(Didn't work with Map folder in the Garmin folder so put it in general directory).

Thanks very much

(23 Aug '15, 03:46) dm501

Unfortunately it doesn´t work for me.

What I have tried: 1. Creating the folder \Garmin on my SD card and copying the "gmapsupp.img" into the folder 2. Creating the folder \Map on my SD card and copying the "gmapsupp.img" into the folder 3. Creating the folder \Map on the Garmin storage (next to the "Garmin" folder) and copying the "gmapsupp.img" into the folder

In neither case I can find the new map on my device (nüvi 255W). Source of my file: (Chile OSM Base map)

Any advice?


edit: now I managed to do it with mapsource. Very good manual: Probably my nüvi had problems with my SD card.

Download mapsource: If you have problems installing it, unzip the .exe and double click the MSmain.msi

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answered 16 Sep '15, 12:16

LNN's gravatar image

accept rate: 0%

edited 16 Jan '16, 12:05

aseerel4c26's gravatar image

aseerel4c26 ♦

Sometimes a different description of the procedure helps try this one.

(16 Sep '15, 14:25) andy mackey

Huge thanks for this- I tried all sorts of things and your directions finally let me load a new map into my Garmin Nuvi. Thank you, Richard!

EDIT: Just wanted to add that I used a Micro SD card to load the new map.

1) I loaded the gmapsupp.img file into a directory I created named "Garmin" on the Micro SD card and slid it into the card slot in the Nuvi.

2) After booting the Nuvi, I went to "Settings", "Map", and "Info", selected the new map and deselected the old/original map.

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answered 22 Apr '16, 01:48

Jaded's gravatar image

accept rate: 0%

edited 22 Apr '16, 01:54

Just to add to Richard's answer:

Garmin maps are simple .img files (files with .img extension). So updating or adding maps is as simple as copying and pasting a file, which has to be named gmapprom.img or gmapsupp.img. In some places, you may find locked files, but there are tools to unlock those.

Once you have your map file, you have two options:

Option A: Use you Sat Nav inbuilt memory Copy and paste your file to your device (/Garmin folder). Once connected to your computer, it will appear as an additional drive. You may not have enough space on your device, but you can remove some files and replace the existent map. You can always make a backup and copy the files to your computer. You can delete the voice files to make room. These probably contain lots of different voices and languages (files with .sum and .vpm extensions) that you never use, so maybe taking up quite a bit of space.

Option B: Use an external SD card If you do not want to remove nor touch the original maps (the ones that came when you bought your device), you can play safe and use an external SD card. You only need to create a folder called Garmin and copy your .img file in this directory.

For more information, including all the steps and screenshots, visit

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answered 09 Aug '18, 14:02

lean's gravatar image

accept rate: 0%

edited 09 Aug '18, 14:03

Hi, here is a, free, program that will manage the map files on your Garmin. You can install more than 1 map. You can choose a more usefull name than just "gmapsupp" :

hth Gys

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answered 11 Aug '18, 08:30

Gys%20de%20Jongh's gravatar image

Gys de Jongh
accept rate: 16%

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question asked: 25 Apr '11, 20:34

question was seen: 362,737 times

last updated: 14 Aug '20, 08:59

NOTICE: is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum