WiFi says scanning, then says disconnected. What's wrong?

I just bought th X10 today, and the WiFi isn't working. In Wireless controls, the WiFi setting is on, and says scanning, then immediatley says disconnected. The WiFi settings shows my network (and after I typed in my router's password, it says remembered, secured). How can I get my WiFi connection to work from my phone?

PS I still have Android 1.6 (and haven't upgraded because the vendor said to let my battery run down before I charge the phone for the first time so the battery will remember the right amount to charge; but if I connect the X10 to my PC to upgrade Android, the battery will charge. So I've been trying to drain my battery quicker - I've been taking videos and playing them, but the battery still isn't low yet!) ?

Any idea?

Please help.

Thanks!

I didn't find the right solution from the Internet.

References talk.sonymobile.com/t5/Xperia-X10/WiFi-says-scanning-then-says-disconnected-What-s-wrong/td-p/43611

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