Hi,
I googled 'dvd266-r1 and found the page I think you were looking at and got the same Error 404- Page not Found.
I then googled 'dvd266_r.pdf' and found this page:
http://forums.2cpu.com/archive/index.php/t-16067.html

If you read through it, they mention the manual for your motherboard:
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Well, the manual for the DVD266u-RN on the web site is the one that comes with the actual motherboard.. BUT.. I took a look at the manual for the DVD266-R. Granted, not the same board, but I thought it would be worth a try.

The manual for the DVD266-R is just one page with some information and pictures.. not much, but surprisingly helpful. The pin layout is different from the one listed in my own motherboard's manual, so I gave it a try. You can take a look at the manual here (http://www.iwillusa.com/support/manual/dvd266_r.pdf)
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So I then googled 'iwillusa.com' and came across this forum suggesting iwillusa.com was hacked and the site is completely down:
http://www.hardforum.com/showthread.php?t=1025312

I even translated a page from Korean with a link to the same PDF but got the same 404 error.
So I don't think the manual is out there to be downloaded, and the fact that the company's website was hacked would answer your question about the Error message, but you could read through the page at forums.2cpu.com and see if what they are discussing pertains to your problem at all.

That's the only way forward I guess, other than attempting to contact the company yourself:
http://www.computerhope.com/comp/iwill.htm

Hope that answer's your question and I'm sorry I couldn't get a copy of the manual for you.

Chris (ziraffa)

Here you go.

http://www.motherboards.org/mobot/manuals/IWill/DVD266-R/

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