I purchased DSL 2640B wireless/router modem combo to replace my 2-Wire 2701-HG-B which suddenly died last week. The tech support guys at AT&T were able to help me connect to the internet through the LAN cable, but even with the security feature disabled, I could not use the internet through the wireless router. I could access the configuration page wirelessly, just not the internet, so I called D-Link Tech support.
Even though I told them I had disabled the WEP encryption, they walked me through disabling it. Then they had me enter the universal DNS and alternate DNS. When that didn't work, they had me contact AT&T to get the DNS from them. AT&T told me they use the universal DNS, that I needed to contact D-Link for help. When I tried calling them again, the system hung up on my twice. I tried contacting them via e-mail and never heard back from them. A few days later, I contacted them again by phone and once again, after I explained to the Tech support representative everything had been done, she tried to walk me through disabling the WEP encryption. I told her I already said I had disabled it. Then she tries to walk me through entering the universal DNS. Once I again, I reminded her that I told her I had already done that. Then she tells me that I need to contact AT&T and ask them what to use. Once again, I reminder her that I already told her I had done that.
Then she tells me I need to contact the manufacturer of my computer to figure out how to disable the firewall. I was trying to connect with a work laptop, and we are not allowed to disable the firewall. At this point, I gave up and bought another 2-wire product. I got it set up in less than 10 minutes with no phone calls.
I'd advise you to return it and try another, more user friendly product.
Bridging a d-link wireless router