My Pfaff is a year old, an Expressions 3.0, and it will not sew with Gutermann thread. The shop I bought the machine from is very aware of this also, as they are not surprised if a customer comes in with this complaint.
It sews fine with Madira, Sulky, and another brand I can't remember, so i just don't buy Gutermann.
Good Luck trying to get it to work, or just decide that machine isn't going to play nice with Gutermann and use other threads with it and save yourself a haedache.