You don't say in your post what kind of problems you are having when you try to print the return label. Without further details it is difficult to advise you as to the correct course of action, but in order to try and be of some use I've tried to hazard a guess as to what may be wrong, with the potential solutions given for each scenario.
1. Paper Jam: Remove the paper from the paper feeder. Open up the printer and see if there is a crumpled up page somewhere within the bowels of the printer. If you have been doing a lot of printing prior to the printer jamming up and causing the page to get stuck then be careful when you get to the metal rollers, as you can burn yourself on these if you are not careful! Should you see a crumpled up page stuck in the printer then pull it out carefully, taking care to make sure that you don't rip the page further. If you do then you could end up with small pieces of paper stuck in the printer that need to be removed, which can be a pig of a job to resolve and will often result in very sooty-looking hands once you've finally cleared the paper jam, especially if the printer cartridge has been rammed in clumsily and has ended up getting cracked! I've experienced this at work whilst fixing a printer for a colleague and it's a very dirty job - if this has happened then the insides of the printer will need to be thoroughly cleaned of all traces of printer toner and the damaged cartridge replaced!
2. Out Of Ink: If the ink has run out obtain a replacement cartridge. Remove the expired cartridge, insert the new one and try to print the label again. If it's just down to an expired ink cartridge then a replacement ink cartridge ought to sort it.
3. Link Between Computer And Printer Has Been Broken: In this case you will need to re-establish the link between the computer and the printer. The process to go through to establish a link between a computer and printer can vary depending on the make and model, but if you refer to the handbook for your printer it should explain how to do this. Once the link has been re-established try and print the label off again to see whether it will work.
In the event that none of the above are applicable and you cannot work out what has gone wrong, then try logging in to your eBay account somewhere else where there is a printer that you could use, such as at work or in your local library. If you can print the label off elsewhere but not at home then the problem may well be due to one of the three problems outlined above.
