Yesterday customers using HP 934/950/970 cartridges using non-HP chips started seeing a "cartridge problem" message on their printers. This is not a problem with the non-HP chips but the Dynamic Security Feature on the HP printers listed below (this does not apply to any printers that aren't listed)

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Product series

OfficeJet Pro 6230 series
OfficeJet 6810, 6820 series
OfficeJet Pro 6830 series
OfficeJet Pro 8610, 8620, 8630, 8640, 8660 series
OfficeJet
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