Stupid noob ?? i apolgise in advance 2.2 problems

[lspec]

Ok so here we go, I have a Orange UK desire which I have unbranded but not unlocked.

The OTA has come through for the phone for 2.2 when I try and install it with my normal SD or my goldcard it goes through the motions and then flash a picture off the phone with a red ? and reboots to 2.1

Here is my Software info

Firmware - 2.1 update1
Baseband 32.30.00.28u_4.05.00.11
Kernel 2.6.29-0cb9f166 htc-kernel@and18-2#1
Build number 1.21.405.2 CL174215 release-keys
Browser WebKit 3.1

I have read a few threads about reinstalling the stock 2.1 rom via HTC sync, I have googled and can't find the 2.1 apk file that has not been modified, can anyone point me in the right direction or another way to install 2.1

Any other help would be great......sorry again for the stupid questions