1. The router has current (latest) firmware.
2. You've tried it without WEP, WAP, MAC filtering.
3. You've tried another router.
4. The machine has no spyware.
Bob
My wife has a Compaq 2596US laptop running WIN XP Home, which came with a wireless Broadcom adapter (card? what do you call it?) built in. We have a D-Link DI-624 router and cable internet.
If the laptop is connected via cable, everything is fine. However, if we try to use wireless connectivity, the laptop reports "excellent" signal strength. After about 2 minutes, however, it reports that there is NO signal. A few seconds to a minute later, it tells us "Oh, look; I've detected a wireless signal with 'excellent' strength." This on-again off-again cycle is repeated until we give up and run a cable.
We have the latest firmware for the NIC and the router. The "help for idiots" supplied by the ISP says the computer cannot obtain a valid IP address from the server, and says the problem might be in the cable connections, the modem, or the NIC. The laptop says the wireless NIC is just fine, thank you. HP/Compaq has a wireless setup wizard, which we attempted to run. It told us that it couldn't help us because we didn't meet the "minimum configuration", but didn't mention what it found lacking. Via e-mail, HP takes one of three routes: either 1] download and install the patches for the wireless NIC; 2] it is the router's fault; or 3] they don't respond at all. D-Link says they can't see anything in the router, and suggests that we either call HP/Compaq or get another wireless device and if IT also has problems, to call them back.
If anyone can suggest a fix, we would be very appreciative. Thanks!

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