iis 6 won't serve mdb file - kpg

hi all,

I have written an asp.net 2.0 app that to allow users to
download files.  It does this by presenting the user with
a url to the file, they click it and save the file to their
local drive.

When the user clicks on an assess file (*.mdb) they get
an error "This type of page is not served" (logged as 403 0)

I know II6 only severs files with a defined MIME type, but
mdb files are defined in the MIME list (by default, I did
not need to add it)

So there must be another mechanism that prevents download.

I am aware that allowing IIS to serve mdb files is considered
a security risk, but this site is password protected and
serving mdb files is one of the reasons it exists at all.

So I have two questions:

1) Why are mdb files blocked even though they are a defined
MIME type for the IIS server.

2) How do I allow mdb files to be served (if not via the
MIME type)?

thanks
kpg