Just got a new HTC hero from 3uk and had a nightmare to get the app market and downloads started just wouldn't work!... after a week in and out off the 3 stores we found the prob. 3Hg have started using a new 6 pin sim card....the HTC and Android OS don't like them at all!!! get it swapped instore to the old style 8 pin sim card. Worked for me!