I just discovered my old 720 in a draw and decided to see if it still worked, all these years later.
It did and the battery still works and so do the maps.
But then I (foolishly) updated it from TomTom home.
Now I get the dreaded "Problem with map, you cannot use this map......"
I had a back up and copied over all the backup files to the TomTom, overwriting all files - no joy.
I've tried using Fastactivate - no joy.
And I also installed Navcore 9.541 by copy and paste - again no joy.

Any suggestions appreciated.

Maybe you forgot to patch the navcore too?

Thanks - I got it working.This time I deleted everything in main storage and removed the SD card.
Then I copied in the files from the 9.541 cab + one map, then ran fast activate.
Last time I got some strange messages with FA 1-2-3, but this time it worked OK and I am up and running again.

Just a thought - why was it zapped when I connected it to TT Home? And is it possible to stop it happening in the future, if someone else tried to update it?

Hello @roggen,

With a patched navcore and a patched map, don't try anymore to connect your device to Tomtom Home. You will be recognized as a cheater.
At once Tomtom Home will erase some files and your gps won't read any single map. You will have to rebuild navcore and map from your last backup.
Navitotal is a safer place for patched units. And delete TT Home from your PC.