One of the recurring issues I run into is the unit is just a few years old and needs new rollers plus a good cleaning. If it's new and jams it's HP problem. Old, I decide if it's worth the hours to find the parts.
Bob
Hello, I recently restarted a thread about HP Scanjet 5590 problems but got no reactions; maybe I need to retitle and refocus after more trials.
The problem is really with the ADF, for me an essential accessory. I can scan a page manually OK.
When I use the ADF, for me essential accessory, it now swallows most of the page then tells me ?paper jam?. Unlike usual paper jam nothing can be seen wrong like pages crooked, scrunched, etc., paper is ordinary and has gone in perfectly smoothly. I easily pull it out (forward direction). I try a second page and it tells me ?an unexpected internal error has occurred? and I should either restart HP director, now done v. many times, restart computer, done many times, reinstall Program from disk which I did once*. Nothing has changed.
I first got (and suspect may have provoked) the problem when scanning flimsy documents of unusual dimensions 15 X 21 cm.
*(Having reinstalled has the disadvantage that the HP disk is pre IE-7 as explained in my other post http://forums.cnet.com/5208-6121_102-0.html?forumID=45&threadID=250934&messageID=2635068
so HP director icons do not appear onscreen? I am now getting around that by a workaround but it is annoying. I also notice that in ordinary scans after clicking ?new scan?? the Accept? request no longer appears and I have to go look for that instruction.
Any suggestions? (If so I apologise in advance I may not be able to come back here for a week maybe.)

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