Unfortunately, the drum kit (and toner) that were purchased were not compatible with the Okidata B411d. The staff was helpful and worked with me to try to figure out why the drum & toner were not working. The conclusion was that there was a problem on the manufacturing side that made the drum (and likely toner cartridge) not function properly in the B411d. InkTonerStore refunded the drum & toner purchase - which was an acceptable solution under the circumstances. Trouble-Shooting Note: I purchased a used B411d, and was initially receiving a similar error message trying to get that one up and running. I found a video from Israel (very little English) that FIXED the problem on the used machine by removing, cleaning and replacing the Front Assembly of the Duplex Assembly. The drum from the used machine worked on my old machine after cleaning/replacing the Duplex Asbly, but your drum would not work on either machine, strongly indicating that your drum IS the faulty part.