Windows 7 64 bit + SONY Vegas Pro 64 bit can not handle AVI file ?

My environment: Windows 7 64 bit + Vegas Pro 9.0d 64bit.
(Windows XP + Vegas Pro 9.0d 32bit handle AVI fine in same machine)
Click AVI file shows "Video: Stream attributes could not be determined"
Tried every codecs but no use, 64 bit codecs also tried too.
Adjust 2 Internal related parameter nothing help.
Options -> shift + Preferences -> Internal
Ignore third party DV codecs - FALSE or TRUE (Default)
Use Microsoft DV codec - TRUE or FALSE (Default)
Still no solution, Of course, AVI file can be play normally in Media Player.

Workaround: Use format converter such as Format Factory to convert AVI to MPG or WMV.

Vegas Pro 9.0e released, Trial Version can be download here.