The why is because it's AC and Star. Now, I don't mean that as if it is either's fault or both because I don't know. I do know that something as simple as installing a printer driver should not be this difficult.
I would recommend emailing Christine Baldwin at Start Micronics at
cbaldwin AT starmicronics.com. She is the one who I always work with. Don't remind her that they loaned/gave me a TSP800II. But, then, I have helped them quite a bit with sales.
Her direct line is 732-623-5500 ext: 509
Just play it up and tell her that Bert said she is the greatest thing ever. Anyway, she is the head of support there, and, given most people have problems with the TSP, I am sure she gets a lot of practice.
The last thing I forgot to suggest is what I did back in great Star failure. I don't know why it worked. But, try going to every computer in your office. If you can get just one to work properly, you can share that one out to all the others.