I am new to this forum and have a similar trouble with the C7280 not working with gentle magenta or magenta. Did this issue ever get resolved? My "Ink System Failure" code was also 0xc18a0101. I'm so glad I appeared more for your remark with the exact same error code. https://customercare-support-number.com/call-1-877-717-6111-to-fix-printer-error-code-0xc19ac252-2/