Vista, citrix web client and saving files to my local disk

I am trying to use my organization's web mail and to save a file to my laptop's hard disk. Under Win XP, once the permissions were given in Citrix (no access / read only / read and write) I had no problem downloading files (email attachments) to my local hard drive.

Now I am using Vista Business on an XPS M1330, with the latest updates for Vista and IE and the latest ICA web client (v10.x). When I log onto my account, then open Outlook remotely to look at emails, I get an error that the disk is read-only. Outside of the citrix web client, saving to the C drive (root directory) happens without problems. If I try to open "C:\Users\ " I get another message that I don't have permission to access that directory.

Any clues to problem? Any suggested solutions?

THANKS!