TomTom 7.910 shows no maps found for 880 maps

I am having problem with a chinese gps,running wince5.0. tomtom 7.910 was running good for 860 map, but map was too old I want to update. So I tried to run 880. 3811 map, but it gives me " no maps found" error. It is indicated in the chart that it is capible with 7.9X.

I really need help on this .thanks.

I also tried to update navi core, but 7.915 7.917 and 7.918 seems have .cab file. and I could not install them on wince. is there a way for me to update tomtom application from 7.910 to any other new version for wince 5.0?

callofjj, on occasions when I have been trying to get Tomtom to work on various sat navs and PDA's, is that sometimes I have found that there can be more than one ttnavigator.bif file especially if you have been trying to get it to work by using different versions of TT so have a look through any folders on your SD card or on the device itself and patch all that you find. Also if you are loading it onto a PDA or similar I have found that the serial number that is in your ttnavigator.bif file can sometimes be different to what your device is telling you so if you can find your device serial Number either on the device or on a label on the case then try entering that into your ttnavigator.bif file by opening it in Notepad, and then saving it back to where you found it, then unlock your map with whatever tool you have already been using.