When accessing Project files on Sharepoint, cannot enter password.

[QFT]

Don't know whether to put this in Sharepoint or Project!

Our users are logging into a terminal server to do their work. Project 2003
is installed on it, and they access documents on Sharepoint. They are not
administrators.

I noticed that when opening a Project file from Sharepoint, the password
authentication box appears while Project is opening, but it is greyed out -
you can move it around, but can't actually select it or enter your password -
and therefore can't open the file. Project's splash screen is up the whole
time and won't go away.

I tried opening Project, then opening the file from Sharepoint - same
result, splash screen and all.

The workaround I'm using is to click the file on SharePoint, and then
right-click, close the "enter password for server" box on the taskbar. This
makes Project finish loading and gives a "couldn't open file - etc" message
in Project, but then when I click the file in SharePoint again, I can enter
the password and access the file.

I don't know why this is happening. Any ideas on how to fix this little issue?