I have a Huawei HG523a router on TalkTalk (UK) and for the last month I have had a problem where it wont connect stating 'Failed to connect to Network'. I can see the SSID and have connected by entering the WEP key and also connected through WPS.
On the rare occasion it does connect, as soon as I attempt to use the internet the WIFI kicks me off.
I now this might be an issue with my router and I have posted a similar post on my ISP forum to see if this is the issue.
If you need any info that might help or make it easier for you all to pinpoint the problem let me know and i will do my best to supply that info.