Can't detect wireless network on desktop but can on laptop

[#1]

Have just moved to Plusnet but cannot detect Plusnet wireless network using USB wireless adapter supplied by previous ISP(Wannadoo/Orange) connected to my desktop PC. Am able to detect other wireless networks (Sky, BT, ...) presumably from nearby houses. The router is not far from the PC (several metres maybe) and a laptop next to the PC does detect the Plusnet network. So PC can detect some networks some distance away, router doesn't seem to be the problem since laptop can connect but cannot use PC and router together. Any ideas please.

[#2]

You can change the wireless settings between 'b', 'g' and 'n' (or various combinations), I don't think it's that likely but it's possible that yours is set to a version that the adaptor is not compatible with.
the 'n' setting on the PlusNet TG585v8 is known to cause certain incompatibilities (it's not true 'n') and is best switched off.  I'd recomend setting it to 'b'+'g' or 'g' only depending on what adaptors you have.  Also, the default security on the TG585v8 is WPA2, if your adaptor is not compatible with that you might need to set it to WPA or WEP though WEP is not particularly secure so you might be better to buy a new adaptor (there are plenty on the net for less than a tenner) in order to have good security.

[#3]

Thanks for your reply, it was spot on. Wasn't sure how to make some of the changes so had to make a call to Plusnet. They did just as you suggested (and changed the channel but I suspect that wasn't absolutely necessary). Thanks again.