Opening attachmetns in OE 6

When I receive an Outlook Express 6 e-mail from a known source, with files
such as *.avi or Excel file attached, I would like to be able to open the
file by either double-clicking, or right clicking on it and selecting
"open". When I do this, a window opens with the filename in it, and clearly
identifies the associated program to run the file.

But, many such instances, which show the associated program to open the
file, do not respond properly when I confirm "open". An error window comes
up stating that the file type in question does not have an associated
program to run it. But the proper program was shown in the prior window, and
going into Windows XP Pro does show the proper association also.

But, when I save the file in question to a folder, and then double click on
it, it opens with its associated program.

Most extensions do open properly when I double click on them in the
attachment field on Outlook Express. But many of them do not.

Is there some option/setting that I have missed seeing, to correct this
situation?

I did go into ToolsOptionsSecurity, and made sure that the virus
protection box for "Do not allow attachments to be saved or opened...etc."
was unchecked. But even with it checked, I can still save attachments. And
unchecked, I still get the same error message . The latest situation was for
an AVI file, and the associated program is the VLC player

Is there some option/setting that I have missed seeing, to correct this
situation?

Ron Hirsch