You can now flash your O2 ROM using x64 Windows 7.
Procedure
1. Press F8 before windows boot (after bios).
2. Select “Disable Driver Signature Enforcement” and boot up windows.
3. Connect ur phone to ur PC / laptop (Phone must be off).
4. The driver Samsung MITs USB sync will be installed.
5. Open Device Manager, double-click on Samsung MITs USB sync and re-install with driver provided below.
6. Choose Update Driver->Browse my computer for driver software->Let me pick from a list of device drivers on my computer->Click on Have Disk and browse to the driver folder and install. (If prompted driver unsigned, ignore and click ok. Driver is dated 2003).
7. Then right-click on Octans Downloader->Compatibility, select “Windows XP (SP3)” and check “Run as Administrator”.
8. Flash as per normal… 
Note*: You will need to re-install the driver everytime if it is not the correct version after a reboot.
I have tested and flashed it numerous times without any issue.
Do not try on vista as I’m not sure.
i8000_x64.rar ( 49.31K )
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2 comments
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March 28, 2011 at 2:05 pm
Indra Suryatama
if i flash my omnia, is my phone book will be erased to?
March 29, 2011 at 1:25 am
dex008
Yes, Of course it will be erased. You better back up your contact and messages using backup tools like spb backup or other backup tool