So we print to a network printer in our office via TCP, and we changed that network's IP addresses.  (We're on a new Class C subdivision.)  We can print from every single Linux and Windows system except one: a notebook running Windows 7.

Windows offered to troubleshoot the problem, and it ran through its battery of tests.  The tests it spent the most time performing were connectivity tests.  After Windows 7 went through the battery of tests, the lone solution it proposed was to make the printer the default printer.

Problem: Can't print to a network printer.

Proposed solution: Set it as default.

"I'm a PC, I can't print, and Windows 7's troubleshooter was my idea."

I double-checked the port setting, and it was trying to print to an IP address instead of a DNS name.  We changed the IP address to a name, and all the backed up jobs printed without a hitch.

For grins and giggles, I started up Windows XP's troubleshooter, renowned as the most ineffective troubleshooting system ever, to simulate the exact same problem:

• Printing Troubleshooter
• What problem are you having?
  • My document doesn't print at all.
• Can you print other documents from the same program, and can you print from Notepad?
  • I cannot print any files, even in Notepad or WordPad.
• Are you printing to a network printer or a local printer?
  • Investigate
    • Message from webpage
    • The troubleshooter was unable to investigate the necessary settings. Follow the remaining instructions on this page to complete the task manually.
  • I am printing to a network printer.
• Can you print from another computer on your network?
  • Yes, I can print from another computer on the network.
• Do you have a printer installed?
  • Investigate
• Is your network operating correctly?
  • Investigate
• The troubleshooter was not able to ping (detect a connection with) your print server. This might be the cause of the problem. Verify that your network is configured correctly and that you are connected to the network.
  • Yes, my network connection is working.
• Is printing paused?
  • No, this does not solve the problem. Or, these commands don't appear in the menu for my printer.
• Is the printer port set correctly?
  • To verify which port that you are using for a local printer...
    • [Ah, there's the problem.]
  • Yes, this solves the problem.
• Thank you for using the Printing troubleshooter.

That's right. The Windows XP troubleshooter was not only effective, but it would've solved the very problem that the Windows 7 troubleshooter couldn't.

Thanks, Microsoft.