I'm having a really odd problem with my Canon i860 printer and I'm hoping someone here can help me out...
The printer is attached via LPT1 to a machine running Windows 2000 and for months was working fine without any difficulties. A couple of weeks ago I tinkered with my operating system files one too many times and the law of averages caught up with me, requiring a repair of the OS. Once I got the OS reinstalled and all the system updates (SP4, etc.) in place, it's running fine again EXCEPT for the printer.
Now, my printer won't print any text when I have it set to perform "Grayscale Printing" (checkbox on Main tab of Properties dialog). Graphics and other drawing artifacts (table borders, etc.) print OK, but not text. If I uncheck the "Grayscale Printing" box, everything including text prints fine.
I've reinstalled the Canon software (programs, utilities, and drivers) twice - the second time after deleting every trace of the old drivers I could find both on the HD and in the Registry. I've "Deep Cleaned" the print heads repeatedly. I've run every diagnostic included with the printer and everything tests OK - Nozzle Check shows that all five print heads are functional and alignment seems OK.
The printer's test page prints correctly if printer settings are NOT set to Grayscale Printing mode, but if they ARE set to Grayscale, only the Windows 2000 logo and the large words "Windows 2000 Printer Test Page" at the top are printed - the rest of the text (printer details, etc.) are missing.
At this point I strongly suspect the problem lies within Windows itself, not the printer hardware or drivers, but I cannot even begin to guess where to look for it. Any suggestions, folks?

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