I would be grateful if someone could advise me as to how to transfer files from one TTom 720 to another 720 using the current sd card that is working fine. For instance do I need to retain the original ttgo.bif and system file currently on the 720 I am transferring to.
The reason I am doing this is the files on the current SD card are now working fine after much experimenting in an effort to overcome the 'Roll Over' bug that prevents acquisition of GPS signal. The TTom that I want to transfer the working copy files from the SD card over to will not acquire the GPS despite trying to carry out all the work that I did to get the system currently on the SD card to work. So it seems to me the easiest way will be to transfer all the contents from the working SD card onto the TTom that I cant get to acquire the GPS signal.
Hope that isnt too confusing !.

Copy the complete content from SD card 1 to the other empty SD card 2.
SD Card 2 in the other 720. Give the 720 a 15 sec reset and start up
till the anoucement you can,t use these maps.
Aktivate the maps and start up the 720 again.

* Holyhead beat me again lol

Btw, TomTom released a new navcore 9.541 for your Go 720 which will address these issues:

TomTom wrote:
Version 9.541
Released on 19 December 2018 This update applies to: XXL Classic, ONE IQ Routes, XL IQ Routes, XL IQR2 / XL Classic, GO 750, GO 750 LIVE, GO 950, GO 950 LIVE, GO 540 LIVE, GO 740 LIVE, GO 940 LIVE, GO 530, GO 630, GO 730, GO 930, GO 720, GO 520, GO 920, EASE, ONE 140, Start
• Maintenance Release.
• This update prepares your navigation device for the week number rollover in April 2019 which has an impact on GPS.

Thanks Hollyhead for the reply. I will try transferring the working system from the SD card to the internal of the 'problem' TTom and hopefully that will solve it.
Hi Fredderf, I have tried the 9.541 but for some reason couldnt get any success with it BUT I did use the .bin file from it and that solved the roll over bug problem. The working copy is on an SD card which I am having to use as a work round for a TTom that has a hard drive failure but still works by clearing the internal of all files and inserting an SD card with all the operating files on it.