Slow accessing network share

Bit of a long question, I have a Windows 2003 server with a network share. Inside that share I have one folder that takes about 2 minutes to move through for one user. The user has access to it by group permissions.

All other members of the group can open the folder fine. All sub folders open fine. Using roaming profiles the user has logged into other computers and experiences the same problem. I have tried rebuilding this roaming profile but the problem persists.

Would rather not re-build the whole user account as this would involve migrating mail files and other work.