For reasons none of us will ever understand, though HP offers drivers for the dc7800 and Windows 7, there are a few drivers missing from the HP download page. Specifically, the HECI and LMS_SOL devices appear, after installation, with yellow check marks (no drivers installed). If the names of these rascals don’t ring a bell, they are identified in the Device Manager – as I recall – as  ”Unknown Serial Port“, and, “Unkown Device“.   It’s something like that – and a problem for pretty much everyone.

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