problems with mkgmap

this will probably sound stupid, but I have a problem creating garmin maps from openstreetmap. I downloaded some data using JOSM and saved it to an .osm file.
I saw that i can convert it to an .img file using mkgmap. I just don’t understand how to do that. Could someone explain it to me in very easy steps?

What exactly are trying to do? What sort of img file do you want? What OS are you using? Have you downloaded and unzipped Mkgmap to somewhere on your computer?
You could start by trying the simple example on the wiki page:
ie run this from a command prompt (in your Mkgmap directory):

java -ea -jar mkgmap.jar data.osm

(where data.osm is the file you saved from JOSM). That should generate a file called 63240001.img.
You will probably also want to set some extra options depending on what you want to do with the img file, most of them should be listed on that wiki page.

what do you mean by running a command prompt in that directory. is that with start\all programs\Accessoiries\ Command Prompt?

Yes, that will start a command prompt. You will then need to change to the correct directory. eg if you unzipped mkgmap to a folder on your C: drive, use a command like:


(change the number depending on which version of Mkgmap you downloaded).
Then you should be able to run the command:

java -ea -jar mkgmap.jar data.osm

Have a read of my introductory guide to mkgmap here:

it doesn’t work. it says “The syntax of the command is incorrect.”

Please post your commandline so that we can see what’s going on. There’s nothing we can do if you’re just saying: “it doesn’t work”

i used an other computer and it worked. i don’t know why it didn’t on mine, but my problem is solved now.