v400 Problem uploading ringtones from computer

I have a v400, Mobile Tools 4.0 (updated) and cable. When I hook up the phone, everything seems to be fine. I can access my contacts on the phone, I can use the phone as a modem, etc. But, for some reason when I try to upload ring tones or pictures, it says it can not communicate with the phone. Once I exit that part of the program, I can still access my contacts, etc.

I'm with cingular. Does anyone know if there is a setting in the phone I need to change to access the ringtones or.... does Cingular block ringtones, etc.