The white screen of death, or can it be saved??

my htc desire wont turn on, or connect to the computer. the screen turns white andre the "htc" logo turns up and it wont turn on or off. If i try to do somthing it wibrates 7 times and stayes the same. what can I do? I can enter the root meny (volum down and turn on phone), and someone at the norwgian htc center sent me an upgrade (3.2.2) and told me I could install it from the rootmeny, but he forgot to tell me how to do it... can anyone help me? -Kirsti-