Authentication prompt while opening Excel/word files from IE8

While opening Excel or Word documents from intranet websites in IE8, we are
seeing authentication prompt and after providing credentials the file is
opening fine. Surprisingly if I cancel the authentication prompt, the file is
still opening fine!! Is this problem related to IE or Office? How to fix the
issue?

I tried following but nothing worked:
-Moved website from intranet zone and added to trusted sites
-Reset IE8 settings
-From Firefox the files are opening fine. FF is downloading file to local
disk and opening it.
-Changed default browser to Firefox and tried to open Excel, file -> open
and gave Excel file HTTP URL

Environment:
IE8 - 32-bit
Windows 7 x64

Never mind. Solution given in following MSFT article worked.

http://support.microsoft.com/Default.aspx?id=943280

Or by getting the computer(s) fully patched at Windows Update...

Chandu N wrote:
> Never mind. Solution given in following MSFT article worked.
>
> http://support.microsoft.com/Default.aspx?id=943280