Can't print over network.

I have a printer on my network that I can't print to regardless of what I do. I'm just going to get as much information out at once as possible, so I'll try to keep it fairly organized. Sorry if any of this information is redundant or useless.

Okay, this printer is a Lexmark 2500 series. Recently, I got a wireless USB adapter, and moved my computer upstairs, removing the wired connection. My printer, which had previously worked, now will not print.

The printer is connected directly to another computer, not the router. That computer, as well as mine, is running WinXP SP3. File sharing works perfectly. When I try to add the printer via the add printer wizard, everything works fine. It will find the printer, and has all the information for it.

Okay, this is what happens and what I've done, and where it gets confusing. This is after I've completely uninstalled and reinstalled the drivers and software. First, I tried installing it as a network printer. It finds the printer, says it downloads the driver, and appears in my printers and faxes as Lexmark 2500 on XXXXX. In properties, the port is set at USB001(described as virtual printer port for usb), bidirectional support enable, and I can change none of the settings. When trying to print with notepad, I get a "the handle is invalid error".

Next, following suggestions on the web, I tried adding it as a local port(\\XXXX\Lexmark2500). This produces a printer that I can freely change the settings on, bidirectional support enable, and the port is \\XXXX\Lexmark2500. The print processor data type is LEMF, and when I try to print, the file is put in the queue, and then I get told that the printer is not communicating. Using any other print processor data type, such as RAW, will result in a "the system cannot find the specified file" error.

Other info:
The other computer we have on the network that is not connected directly to the printer, which is a laptop running Vista, can print over the network. The computer that is directly connected uses the RAW data format. The drivers are the newest version. The Print spooler service is running.

Okay, I think I've got all the information I can provide, so thank you anyone who helps me with this, and if you need any more info, just ask.