ASP Download issues that only happen on some computers

Hi,
I have made a company page for the YWCA that allows them to upload and download there similarly used files, so that they can be used from all locations. The page is done and works flawslessly except on 2 laptops and one desktop that I have tested it on (I have tested it on a total of 10 PC's and it didn't work on 3 of them).
Basically what is supposed to happen is when they click download, it opens a file browser and then they click the file they want and it will pop up the usual "do you want to save to disk or do you want to open from current location" windows popup. For some reason on these 3 machines the file browser will open fine, but when I click on a file to test the open or save thing won't come up.
I know it isn't an error in the code, and I apologize but can't paste the link as it is secure. I just was wondering if anyone has ever had any similar issues and what might be some options to try. Thanks!

In IE Tools under the security tab for the internet zone, under custom level, there is a place to enable or disable downloads. I'd be pretty sure that that setting is disabled. Especially if their security setting is set to high.

Awesome, thanks, I'll give that a try and let you guys know.