iPhone 3G won't start, iTunes can't find the phone

[blahi]

I upgrade iPhone to iOS4.0 but sometimes iPhone freeze when I playing games or using multitasking (white screen and then turn off) and it takes about 20 minutes to turn it on. So I wanted to downgrade it to 3.1.3 again (problems starts when I install iOS4) but if I connect phone with PC and iTunes automatically start sync, iPhone turn off, so I done DFU on it but iTunes tell me error 1 (no device recognized) iPhone is off and won't start, iTunes can't see it. I can't do nothing, about 5 hours I trying HOME+POWER buttons or 3 sec POWER, then HOME and POWER 10 sec and then only HOME but nothing working.

So please help me I think this is only SW error because every problems starts when I upgrade SW to iOS4

Thank you and apologize for my English I am not from English speaking country

 

[stormchaser]

Are you getting error 1015 in iTunes?

 

[booch221]

similar problems

I had similar problems--not exact--but close. I could never turn my phone after the attempted upgrade to IOS4. See this thread for all the gory details:
https://forums.macrumors.com/threads/951728/

I took it to the AT&T store and spent a long time on the phone with Apple Tech Support. Nothing worked. Apple had to send me a new phone. It arrived today. I will not put IOS4 on it at least until version 4.1x comes out.

Good luck to you.

 

[blahi]

Are you getting error 1015 in iTunes?

No I think it was error 1 (yes only 1) but I can't check it because phone won't turn on and iTunes didn't see it
I think about it and only idea that I have is that the phone wonn't turn on because unsuccesfull DFU mode when I tried to restore it( I mean DFU mode wonn't let my iPhone start, becouse iPhone was in DFU but iTunes have some error and phone freeze in DFU, I hope you understand)

EDIT: iTunes tell me something like: Device can't be recognized and after it phone wonn't start and iTunes do nothing

 

[blahi]

No one can help me ?