Workstation has 'insufficient memory' error when attempting to add attachments

A users workstation gives an 'insufficient memory' error when going to add attachments from outlook, the roaming profiles drive on the server has 2.7gb of free space and the users hard drive has about 5gb of free space on it, I'm not sure if this is connected but the user normally loses access to their active desktop shortcuts at the same time. Could this be a RAM issue? or maybe a memory leak? None of the other users experience the problem, user is running windows xp and office 2007, server is windows server 2003 sbs.