Here's the situation: laptop is Windows XP SP 3. Wirelss router is Thomson Speedtouch 780WL. I can connect to the internet fine with my laptop using an ethernet cable into the back of the router. My Android smartphone connects fine to the Wifi, but my laptop won't connect to the Wifi. I've tried repairing, disabling and re-enabling the wireless but no joy. This is using the Windows XP wireless client.
I guess, given the fact that my smartphone is working fine, that the problem is with my laptop. Yet, I've connected to hundreds of wifi points before with no problem.
One important factor that I think could be an issue is that recently, while in the UK, I installed one of those 3G USB dongles to use mobile broadband. It was from a company called O2 and it selfishly installed its software (a horrible thing called O2 Connection Manager) which not only managed the 3G connection, but also decided that wasn't enough, that it should also manage my wireless connections. However, it did work fine with any wifi connections I tried, but it seemed to depend on having the dongle plugged in (which I found infuriating). The problem now is that I am no longer in the UK, so I can't use the dongle. Could this be the reason behind my problem? I've no problem uninstalling that O2 software if people think it's the right thing to do.