I am "locked out" and can;t add a Dell laptop.

If everything works properly in all rooms but one, there must be something blocking the signal between the router and that particular room, or
if it the farthest away from the router that room could be at the end of it's signal. You could try just relocating the router to a more central point and sometimes just moving it a short distance can change the whole deal? Try it, what could it hurt?

Hi, The default IP for most D-Link routers is 192.168.0.1. Even if you're locked out, doing a hard reset to the D-Link AP/Router will put it back to default (but of course that would delete all settings including your security codes (which I presume you're referring to the WEP or WPA and/or MAC address filter)). This would grant you full access using the web configuration utility. Follow the instructions of your manual which is also available from the D-Link website or post again if you need specific step by step instruction. Some probable reasons you can not perform the above is if: 1. Your ISP has given you a very specific configuration and/or static IP add & you do not have the details; and/or 2. The AP/Router is physically not accessible to you; 3. There are other clients connected to the AP/Router that you can not re-configure if you do a reset; 4. You do not have administrator privileges to modify the AP/Router's configuration. Post back also with info on: How many wired or wireless clients connected to the AP/Router and what is their typical IP settings; Try to get your ISP/WAN settings; and availability of manual. Good luck and kind regards.