Question : Problem: HP ScanJet 5100C Not Working

I recently upgraded my system to Win98 and loaded the HP driver upgrades, but I can't get my scanner to work.  When I check the device in device manager, it is identified as HP C5190A and says it is working properly.  However, when I click on the "Scanners & Cameras" icon in Control Panel and then access the properties for HP ScanJet 5100C, it says the status is unavailable.  If I launch the Precision Scan software from HP or try to test the scanner from the properties box, my system crashes.  Any suggestions?

Answer : Problem: HP ScanJet 5100C Not Working

Most likely you do not have a HW problem but 1st do a HW test anyway.
HW test:
- disconnect parallel cable and power cable from back of scanner
- remove scanner lid/cover
- lock and lock scanner multiple times, then ensure scanner is fully unlocked
- press front green Scan button (keep pressed), then power scanner
- front green power LED (right hand front side scanner) must be On and scanner lamp must go On and start to move
- the lamp of most units will move up/down ca. 1 inch (endlessly, untill you power off the scanner); the lamp of some (older) units will move and play a melody and finally return to the back of the scanner
When this HW test fails, contact HP Customer Support for resolution options.
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When HW test is OK, perform a Scanner diagnostic test from the SW (Start, Settings, Control Panel, Scanners & Cameras, Properties, Test Scanner or Camera).
When the SW test fails, click Details, make a print screen (ALT+PrintScreen will copy the message to the Win98 clipboard, paste it into e.g. MS Paint and save the file) and contact HP Customer Support for resolution options.
When the SW test is OK, most likely you do not have a scanner HW but PC/Win98 configuration problem.
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Tips when scanner HW is OK:
- ensure scanner directly connected to LPT1 (do not connect printer to pass through port of scanner yet)
- ensure PC Bios LPT1 settings are optimal for this scanner: IRQ=7 + IO base address = 378 + mode=EPP; when you can choose between EPP1.7 and EPP1.9, ensure the mode is set to EPP1.9; when you cannot set the mode to EPP(1.9), try ECP/EPP(1.9); when you cannot set the mode to ECP/EPP(1.9), try ECP
- find/delete all temporary (*.tmp) files on your system
- your parallel port driver will be properly listed in Device Manager under SCSI controllers as HP EPST adapter (without excl. mark) and I assume in Dev Man under Imaging Devices you have the scanner (model #) without excl. mark; try adding (double-click the) HP EPST Adapter, Settings) following switches to the EPST driver: /di; when this does not work, try /ni; when this does not work, try the combination /di/ni.
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Are above assumptions correct and my tips solved your prob?
If not, let me know and I'll give you some more.