The power light and all color cartridges lights are blinking. According to [URL=https://support.hp.com/us-en/document/c01628597#AbT27]HP support[/URL] such light pattern means that those "cartridges are faulty or need attention" and the solution is:\n[LIST]\n[*]reinsert cartridge, or\n[*]replace the cartridge\n[/LIST]\nThrough out the years, whenever there was a cartridge issue I just had to override it (resume button or power+resume x3). Unfortunately, now is different (although there is no visible damage or other known reason). Even cleaning the gold contacts of the CISS chip made any difference.\n\n[B]Question[/B]\n[LIST]\n[*]What might be causing such issue?\n[*]Any way to solve it without replacing the cartridges with new ones (extremely expensive)?\n[/LIST]\n\n_______________________________________________________________________________\n\n[B]ADDITIONAL NOTES[/B]\n\n[B]Firmware[/B]\nI've already executed [URL=https://ftp.hp.com/pub/softlib/software12/COL34350/mp-85040-2/OfficejetPro8000_R1006BR_ENG.exe]HP Officejet Pro Firmware[/URL]. The firmware was already the latest one, even so I required it to be updated. \n\n[B]Damaged/dirty component/sensor[/B]\nI've already cleaned them with isopropil alkohol.\n\n[B]Bad cartridge[/B]\nThey were all installed in 2010. Never had any issue with them. Recently all 3 decided to fail simultaneously. However, there are no visual damage and the gold contacts were also cleaned with isopropil alkohol. \nI've also executed [URL=https://ftp.hp.com/pub/printers/hppsdr/HPPSdr.exe]HP Print and Scan Doctor for Windows[/URL] which shows: \n\nblack | yellow | magenta | cyan\n:-\-\-: | :-\-\-\-\-: | :-\-\-\-\-: | :-\-\-\-\-:\nready | failure | failure | failure\n\nHowever, the sensors can precisely pinpoint whether the cartridge is missing or is a failure. For example, removing only the magenta would show:\n\nblack | yellow | magenta | cyan\n:-\-\-: | :-\-\-\-\-: | :-\-\-\-\-: | :-\-\-\-\-:\nready | failure | missing | failure\n\n[B]Cartridge compartment[/B]\nI've already check that several times: [URL=https://imgur.com/a/sf54Jsv]cartridges compartment[/URL].\n\n[B]Bottom of the cartridges[/B]\nI've already check that several times also: [URL=https://imgur.com/a/Akw1YAu]bottom view of cartridges[/URL].\n\n[B]Hard Reset*[/B]\nI've already tried that with several different black cartridges and several different black/yellow printheads: [URL=https://imgur.com/a/TbBGj0X]cartridges and printheads[/URL].\n\n(*) Fully power cycle the machine by shutting it down, take out the cartridges, unplug it from the power source, and pressing the power button 5-10 times, and then starting it back up.