Prints get rerouted

We're having a problem with our printers. When we print from an application that's run via Citrix, and the printer that was selected cannot be found on the network, the print is re-routed to another printer. This other printer is in fact a label printer and as a result a huge amount of labels get wasted. All printers are installed as network printers, and we cannot find out why this particular printer is always selected if the correct printer cannot be found. It is not the first IP address, and it's also not the first printer alphabetically in the printer list on the print server.
We've tried installing a dummy printer on the LPT1 port of the print server which appears at the top of the list, but that also doesn't help.
If anyone knows anything that could help us with this problem we'd really appreciate it.
Thanks.

 

If the printer can't be found, why is it listed in the first place?

We use vmware view for our thin clients. I will say, I've dabbled in citrix about 4 years ago. But, we like vmware's solution better.

If ye disable the label printer, what printer gets printed next?

Are all these printers on the same subnet?

Oh, and btw, welcome to majorgeeks!