I have just fixed the Epson "toner waste bin full" warning in the Print Queue windows this morning!.
Firstly I thought I'd check the printer drivers on the Xserve through which the clients print via IP. I opened print set up and the Options Supplies/driver and selected "Select Printer Software" where it showed duplicate drivers for the affected printers. I looked in the Printers/PPDs/Contents/Resources and found the driver existed for the Epson C9100/C9200 in the en.lproj and the top level of the Resources folder. I deleted the drivers from the Resource folder top level and then forced all the Epson printers to select the driver from the en.lproj folder(as I assumed from previous occasions this is always the correct file path for PS drivers) using "Other" drop down menu in the Driver window in Options supplies/driver. As soon as I printed the "warnings" cleared on all the printers queue windows. Why the PS drivers existed in "duplicate" I don't know but its certainly cleared the problem now. Whilst this error warning situation didn't affect printing output etc it was good to be able to solve the issue!
We have just updated our servers to 10.6.8 from 10.6.7 and all the Epson IP printers colour and mono (mainly C9100/9200 models) on the network are showing "ink/toner waste bin full!!" or "OPC near the end of life" warnings. Although this hasn't stopped or affected printing(as far as I know yet) its an annoying bug that seems to have been caused by the 10.6.8 update. Other manufacturers printers on our network arent affected i.e.konica minolta.
Have there any other users been affected in the same way that you know? I have seen other posts that seem to affect OKI printers warnings and some cups file fixes for those people. I have scoured the internet for any fixes for Epson printers but nothing as yet. Apple need to get this sorted as its leading to a lot of unneccessary concern for reordering consumables when not actually required.

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