you tried official Nokia Software Recovery Tool?
start NSRT and select "My phone does not start up or respond option"
HTC HD2 * download Pdaimatejam ROM's + radio's
WP7 ROM Install Tutorial v2.5
Battery saving tricks for HD2
Change Live account region - https://live.xbox.com/AccountMigration
Gmail/Google settings, sync and calendar under WP7.8
My devices: Nokia Lumia 920 developer unlocked, HTC HD2 (sold), GoClever TAB T76 GPS TV
I spent half my money on computers, smartphones, alcohol and girls... The other half I wasted.
(modern version of W.C. Fields quote)