I have lately been having issues with a customer that is runnning Terminal Server 2003 Enterprise. This customer has multiple remote locations that have point of sale pc's with receipt printers attached to them. The point of sale system is a windows program but it uses a DOS printing system/interface and it must print to an lpt port. Here's the way I have these setup in order to print receipts:
Users login to the terminal server and their pos software starts automatically. The receipt printer follows the user's session to the server. On the server I have installed the drivers for the receipt printers. The receipt printers show up in "printers and faxes" on the server whether the user is logged in or not. I have the receipt printer shared and then when the user logs in I have a batch file that uses net use to map lpt1 to this shared name. This works great about 90% of the time. The rest of the time the mapping doesn't work and the users can't print. The users scream and yell because they don't know it's not working until they have customer waiting for a receipt. Sometimes the mapping may be lost during the session but I can't really verify this for sure.
My main question is: Why in the world does this work great and then all of a sudden give me problems? How can I make this stable?