Large white X in red circle flashing

oops looks like you need to reset it and lose your settings etc hope they are saved somehow. see this link to find out how http://uk.support.tomtom.com/app/answers/detail/a_id/1898/~/navigation-device-not-starting-or-displaying-a-cross

youll need to reload the firmware

that should fx it

hi. i suggest to try a soft reset first. go tomtom.com select support search for reset select softreset select your device do as told when this is not enough search in tomtom for start up and read wht to do.

Can be sofware problem or internal memory.
try to conect to pc if you see the dataa from the tomtom is just software if not can be from memory,if you dont know how just send it to a repair centre.
\try this www.satnavservice.com

First turn your firewall off (if you have one). You need to go into your 720 with the TomTom Home software and erase the downloaded software (with the remove items from my device) and reset the device (little reset button under the unit keep it pressed for 5 seconds), place it back in the cradle and restart your computer and than restart the 720 , bring the TomTom Home program up, and when the TomTom Home software in your computer restarts and detects the 720 it will tell you that you need to update the application, if it doesn't than you force the update by going to the add maps option, select items on my computer, select applications and press the add button, when done, go back and to device (option in top of your screen) and select disconnect device, restart your 720 and it should be back to life with the upgraded software.

http://www.tomtom.com/support/index.php?Language=1&query=red+cross&FID=1898

The flashing red circle with the X is a result of the unit becoming disconnected before all data was sent to the device. TomTom has a solution for it on their website here

http://www.tomtom.com/support/index.php?Language=1&query=red+cross&FID=1898

eave on charge for two hours, then with the SD card out (if it has one) hold down the reset button at the back of unit for ten seconds and then the 'on' switch for ten seconds.
STEP 1
Connect your TomTom to your computer via USB and open up your Windows Explorer and go to the drive. (It will be listed as TOMTOM (E) or some other drive letter).
Copy the Yellow Folders one by one to your PC. Ideally, save all the folders under a new folder that you name.
You may find that the folder ttntools and gns may not be copied. This is o.k. if they aren't.
STEP 2
Format your Tomtom via MY Computer.
STEP 3
Copy the Yellow Folders from the backup you made in STEP 1 back to the TomTom.
STEP 4
Open TomTom Home
Click on Upate Now.
Install the latest update onto your TomTom.
Once installed, switch your TomTom off, then disconnect if from the PC.
Thats it. From now on, make a full backup using TomTom Home prior to any updates.
Also note, that copying all the files will take some time.

Hi, I am back, just got the problem solved, I called their tech support at no charge (866-486-6866, Glen) , really good service.
First turn your firewall off (if you have one). You need to go into your 720 with the TomTom Home software and erase the downloaded software (with the remove items from my device) and reset the device (little reset button under the unit keep it pressed for 5 seconds), place it back in the cradle and restart your computer and than restart the 720 , bring the TomTom Home program up, and when the TomTom Home software in your computer restarts and detects the 720 it will tell you that you need to update the application, if it doesn't than you force the update by going to the add maps option, select items on my computer, select applications and press the add button, when done, go back and to device (option in top of your screen) and select disconnect device, restart your 720 and it should be back to life with the upgraded software.
Hope this helps
Aldo