See this thread -> http://forums.us.dell.com/supportforums/board/message?board.id=S2500&message.id=3914

SkariMari,

Thanks for the info. You say: "It sounds like you need to enable scanning over the network on the printer's operator panel. You will find it under the "network" subheading."

But I cannot find it. Can you give me more info ? Thanks.

I finally found the problem. We have our internet connection on the same computer, and not on the router (a personnal choice). With 2 network cards in the computer, the scanning software is bugging during the installation, right after we put in the user and the password, we get "unknown network error". When we turn off the network card with the internet connection (just leaving the network card for our local network), we can successfully install the scanning software and scanning works. But we have to turn off the second network card everytime we have to scan.

Wow, that's a weird one. Have you got internet connection sharing enabled? Or it could possibly be due to a firewall setting. I'm glad you found a workaround at least.
I gather you found the 'enable network scan' option in the menu. (For anyone else, it's in Network Setup -> Network Scan on the printer menu. I think.)

Yes I have the internet connection enable. It is a strange problem, related to the Dell scanning software. Thanks for your help.