I have a Dell 968 printer. I'm coming here for support because you guys will probably be more helpful than them.
The problem is that all pages are coming out with faded, incorrect or 'striped' (on the alignment test sheet it isn't a full thick block) colours. I have replaced both the colour and black cartridges multiple times, but the problem still persists.
For example, here is a picture I tried to print. Here is a scanned copy of the result. Here is also a scanned copy of the alignment page (upside down, I just realised) - taken just after fresh cartridges were put in.
It looks like the drivers are confused or something. That's the only thing I can think of (other than hardware failure) that would cause a printer not to print correctly. I'd attempt to update/reinstall your drivers. If that doesn't help, try using the printer on another computer with a fresh driver installation. If it still happens on the other computer then it's probably a hardware failure. You could try having it repaired but you're better off getting a replacement.
You might also want to try the customer service line. Granted they take forever but they've probably seen this issue before and can tie it to a specific problem.
The Dell users forum has a very experienced and helpful user (pudgyone) than can assist you with Dell printer problems.
However, that is usually ink cartridge problems. One problem we see on the Dell users forum is either dots missing in the printing usually caused by clogged or partially clogged print heads (the print head is built into the ink cartridge). One common problem is clogged heads due to the ink drying out at the head and even new "Dell" branded cartridges can do this (As the Dell's are made by Lexmark for Dell, the Lexmark cartridges have the same problems - and the Dell cartridges are made by Lexmark for Dell).
One thing to try, soak the nozzle end of the cartridge(s) in a shallow pan of warm (not hot) water for about 10 minutes. Blot the nozzle end dry and reinstall and do a test print and see if this helps.
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