Won't print to right tray

First you need to verify that tray 2 will print from diagnostics test. Use the arrow keys to scroll down to diagnostics and press arrow key, then use arrows move to paper path test and press arrow again. The default paper path test is tray 2 single copy so just select print paper path test and see what happens. If printer prints from tray 2 then we know tray 2 works and that means you either have a print driver that is forcing printing from tray 1 or your settings on the printer for tray 2 are not correct for what you are printing. Check to make sure the paper size shows correctly and make sure that the switch on the right side of the paper tray towards the back is set for standard and not custom.

Slow printing I have a Laserjet 4200

This should be set automatically by default. If you are getting no print from tray 2, you may just have worn out pick up rollers. You can go into the menu and scroll to paper handling and you can make adjustments from there

1. Background
   • HP provides details of the problem on its website. The problem usually occur on PC laptops or when printing across a network. HP offers several fixes for the problem.
     
   Software
   • First, check your Windows print queue and ensure the printer is not set as "Paused" or "Working Offline." This can often clear the problem and resume your printing.
     
   • 
     
   Resolution
   • The problem can also be caused by printer driver issues. Try uninstalling and reinstalling the printer driver. Connecting your printer directly to your computer using a parallel cable may solve the problem, but this may not be practical in all cases as many modern laptop computers do not have a parallel port.
     

Instructions

1. • 1 "Power Cycle" Your printer. Shut down the printer, unplug the power cord from the socket, give it 5 minutes, plug it in again and turn it back on. Try to print.
     
   • 2 If the printer still won't process a job, shut down and restart your computer.
     
   • 3 Check your printer cable connections to the computer.
     
   • 4 Check the printer for any paper jams, check the trays, and also pull out the toner cartridge and/or remove any paper jam, if you find one. Put the cartridge back in. Then try to print.
     
   • 5 If after completing the steps above, the printer is still not working, click "Start," then "Settings," click "Printers," and the printer folder will open. Make sure your HP LaserJet 5 is selected as the default printer.
     
   • 6 Double-click your printer, and delete everything from the print queue, canceling all the print jobs. Close out the queue.
     
   • 7 Right-click on your printer icon and make sure it's not offline. If it is, then click "use this printer online."
     
   • 8 Right-click your printer, and click properties. Make sure the right port is selected for your LaserJet 5 Printer. If you are using a parallel cable, you are most likely using an LPT port; if USB, then look for a USB connection in the list. If the port connection is correct, try to print again.
     
   • 9 It's still not printing? Click "Start," then "Control Panel." Double-click "Programs and Features" or "add or remove programs," uninstall your Laserjet printer software, and restart your computer.
     
   • 10 Insert your Laserjet software and driver disk. Proceed to reinstall your printer software and drivers. Then test the printer again. If it is still not working, you probably will have to seek professional assistance.
     

You've got big problems.
You need a tech to take the printer apart.
There is no way that you can get all the labels out without dismantling.
You were using tray 1 to print the labels!!!
If you were using tray 1 then most likely the label sheets are bad.
If you were using tray 2, then you caused the problem.
Good Luck

IS THE PRINTER CONNECTED TO YOUR COMPUTER ? Also try putting paper in the manual feed tray in the front of the printer.

Google "Network printer troubleshoot"
http://www.google.co.uk/search?hl=en&q=network+printer+troubleshooting&meta=
Lots of help depending on your OS

Are you using Window 7 64 bit or 32 bit? Re-install drivers appropriate for that version of your operating system. Also look at the "Paper Handling" section in the printer menu. Be sure both trays are set for "Plain" paper.

1) When the printer receives a print job, it selects the tray by trying to match the requested paper type and size with what has been loaded in the trays. Using an “autoselect” process, it searches all available trays for the paper that satisfies the request, starting with the bottom tray and ending with the top tray (tray 1). The printer begins printing the job as soon as it finds the proper type/size.

2) If paper is loaded in tray 1 and tray 1 is set "TRAY 1 TYPE=ANY" and "TRAY 1 SIZE=ANY" on the
Paper Handling menu, the printer will always pull paper from tray 1 first.

Are there settings on the control panel of your printer?
Is the tray 1 the MP tray? (The one that flips towards you)
If so, can you change the settings of the Tray 1 to Envelope on the control panel?

I hope this helps.