1) Which map are you trying to activate? Is it Central_and_Eastern_Europe_890_4222 or a different map? If you used a different map the meta may not be available.
2) Remove the mapsettings.cfg file from the map folder. Test.
3) Remove the .dct file(s) from the map folder. Activate the map again and test.
4) Did you also patch the navcore?
5) Which tool/activator/keygen did you try? Did you use the latest version?
6) Did you upgrade the navcore from a previous version or was this a clean install?
7) Best guaranteed solution is the clean install tutorial which fixes nearly all problems:
TUTORIAL: Clean Install - How to install the latest map and navcore from scratch!