Webuser Forums: Can't get wireless access to Internet

I have an SMC Broadband wireless router and this works fine, providing internet access to my main PC, which is wired directly to the router. On my second PC I have a D-Link USB Wireless Adapter, to provide wireless access to the router etc. This worked fine in the past but has stopped working. I've tried uninstaling and re-installing the USB Adapter and software but it makes no difference. On my remote PC, I get the message "Ethernet adapter Windows Network Connection, Media state: Media disconnected" and I can't ping to the router from the remote PC

Sounds like the wireless connection is just not working. But everything is in the same physical position as when it did work. Also, the same USB Adpater works fine when connected to other laptops in the house etc.

Can you suggest anything I could do to get to the source of the problem?

Thanks for your help.