1. Make a complete Explorer, not Home, backup of your unit's contents. Ensure hidden files/folders are showing.
2. Go to the location of your downloaded map. you'll find it in this location:
C:\Documents and Settings\yourname\My Documents \ TomTom\HOME\Downloads\complete\ map\
your_map_name
(Substitute your specific map name every time you see your_map_name in these instructions.
It's a cab (compressed) file.
3. Within the compressed cab file, if you look at the contents, you should see a your_map_name.zip file, perhaps a couple of .gif files, a your_map_name.toc file and, importantly, an activation_map.cab file.
4. Use Winrar and extract the contents of the your_map_name.zip file into the current your_map_name map folder on your unit. If you don't have a folder called your_map_name, then create one using Explorer.
5. Then, extract the file in the activation.cab file into the same your_map_name map folder on your unit. If you see a .TLV file, it should go into a folder called 'map' (no quotes) on your unit.
6. Make another Explorer backup of the unit's contents to a different folder on your computer.
7. Disconnect the unit PROPERLY from the computer using the Safely Disconnect icon in your notification area of your desktop.
You are done!
Note to Windows 7 users who upgraded from XP.
You may find your Documents and Settings folders 'locked'. If so, the information here may help:
How to unlock Documents and Settings Folder in Windows 7 | DPJ Online Blog
