unable to access a shared folder thru outlook

[corchi]

Hi,
I am turning to you guys because we have a conundrum, we have a network where we have a filer system running. Well some of our users are having issues opening up outlook and then choosing attachment and accesing a shared folder which they have rights to being in the same group as the other users. we have checked security made sure everyone was in same ou and even tried from different desktops. any ideas all helpwill be appreciated.

sorry forgot that pertinent stuff
1. windows xp pro systems
2. domain with ou's
3. yes the folder can be accessed from anywhere else just not from outlook
4. just the message that you can not access this folder pleae contact your admin and its only happening to some of our users in the same ou with the same user rights and others can access it normaly