Here's my scenario:

The router works fine for all wireless computers. Connects fine so problem doesn't appear to be with router itself. I have the router connected to my Comcast modem. I work on a MAC.

My tenant lives just below us - only a wooden floor separating him.

He uses the WUSB54G adapter that came with the Router.

For months it has worked well for him in the past using his old HP computer.

He even takes the adapter and HP to the coffee shop and can get onto their networks using the Linksys adapter. Adapter is not broken - in good shape.

Router is in good shape. 

Recently he cannot connect at home. 

No devices are near the router or any changes to environment. 

No changes have been made to the settings for the router.

Is there Firmware that needs to be updated for the adapter?

What do you guys think is wrong and what can I do?

Can I do the fix remotely or must I be at home to help?

Thanks,

Sunzanna