Walker - I have been experiencing the same issue with my LM cartridge on my 7900. One time after removing and reinserting my cartridge multiple times it had no effect whatsoever. In frustration, I turned it off. The following day I decided to go a try and second round. It worked just fine. Today, I went through the same procedure again. This time I turned the printer off and it worked fine after taking the cartridge out and reinserting. Is there a way to correct this problem without having to do frequent maintenance on this one cartridge?
Other information - The cartridges I am using were new replacements when I converted to the "new" inks. I've never had the problem before with any cartridge. BTW the new inks and the fact it is one pass when using GO is well worth switching to at the earliest opportunity!! The shade choices are great, too.
The other problem is more irksome. for some reason my printer now loves doing cleanings on a frequent basis even though my auto check feature for clog detection feature is turned off. It didn't happen with my former cartridges. Also, the warm medium ink in the LM cartridge slot is being used at an incredible rate. The ink is being used much faster than the GO cartridge. Most of the inks are now down to about to the 3/4 full level including GO. The warm medium ink is now down to the 1/4 full level. I cannot account for why that shade would be surpassing even the GO usage . Could it be my LM cartridge is defective?