To find the version numbers of your active map and your software:

On older TomToms running software version 7 or 8)
(This is only for the models where you can see the satellite reception strength on the status bar. If not, see below)

1. If you still have old software where the satellite reception strength is shown on the status bar, tap the signal strength bars:


(If you don't see the signal strength bars you either need to select them in "status bar Preferences" or you may have a newer model running version 9,10 or 11 software..... in which case, see below)

2. Tap the small box on the right with "version" and a number (this is the SOFTWARE version, not the map):


3. The next screen should give you a whole screen of information including the hardware model name, the software version (and build number in brackets) and the map version number:


If you have more then one map installed, use Change Preferences/Manage Maps/Switch Map to change to the next one before repeating the above steps to see the version number of each map.

One final note, although it might be tempting to do this while using the on-screen emulator in Home ("Operate my Go"), please don't... it tells lies!!

On Newer models running software version 9 and above
(all models now on sale, and as first seen on the GO x50 models)

These have a menu item to show the details.

The item you're looking for is "Version information'"or "About my device".
Some models, such as the Go x40 and x50 ranges, have this in the main menu (usually on page 3).
Others, such as the XL, Go 1000 and 1005 have it on the "Change preferences" or "Settings" menu.
And the most recent have it as a sub-section of an item in "settings" called "Status and information" or "Me and my Device".

Whatever the route to get there, the info will be shown on a screen very similar to the one above..

"Last Resort" method
For models where you can access the storage memory using Windows (NOT Go1000/2000 or Start 20/25 or VIA series) you can find out which software you have by connecting it to your PC, opening your device like it was a disk drive, and looking at the file called ttgo.bif.

Use your favourite text editor or word processor to open it (Notepad will do).

About 9 lines down, you'll see a line like this:


That example corresponds to v9.430 software
Andy_P, Dec 10, 2011