Thread: Using TMC in Garmin nuvi for free

Originally Posted by RioGrandeBlood

I generated the unlock codes for Bulgaria, Ireland, and Greek at home as well as the pan european codes several weeks before all working correctly. After several attemps (unlock code incorrect length, maybe my mistake) all three codes (Bulgaria, Ireland, and Greek) were shown in my nuvi 1255 as well as all the others with lifetime abo. But when I disconnected the GTM 25 and connected everything at home and in my car only these three stayed completey disappeared til today. Why? Any help is appreciated.

Because signatures are initially in volatile memory and then are recorded in non-volatile. You have reached the maximum number of signatures, supported by non-volatile memory of gtm25, so they disappear on startup (or finalization) when would be recorded .
If the signatures are official, the firmware 3.10 of GTM25 theoretically extends the maximum number supported, but not upgrade if the codes were generated by Jetmouse. Unfortunately using Jetmouse to delete signatures not solve, since it only hides them. Do not know solution to effectively delete signatures. I have a GTM25 with the same problem.