More of a personal note than anything else.
You may after a while on Android ICS and above experience an issue where the Wi-fi fails to connect to any wireless network. The symptoms are fairly specific, the wi-fi manager will show an attempt to connect, then "acquiring ip address", then it will briefly show "connected" before repeating the sequence. Theres a lot of different fixes offered for this on the web including the apps "Wifix manager" and "FXR Wifi Fix and rescue" on google play, however neither of these worked for me and may actually be intended to resolve different issues.
The issue appears to be with the DHCP files the android keeps. For unrooted users this is problematic as they cannot see these files so this fix only will be useful to those of us with rooted phones. the following worked for me on my Xperia Arc.
- Make sure you have a file explorer that can view files as root. Many claim to do this (andro zip, astro) but don't seem to actually ask for root permission and I couldn't find a switch or setting to get them to do so. So I ended up using ES file explorer. To make it browse as root hit menu -> settings -> Root Settings and tick all the check boxes. NOTE: this will allow you to mount your root partition as writeable so be very careful about how you proceed from here. You could break your OS. I claim no responsibility for you cocking this up.
- Use the file explorer to navigate to the root (/) directory of your phone. You do this by pressing "up" in the menubar several times.
- Once there navigate down through data/misc/dhcp
- Delete all the files in that directory.
- you should now be able to connect normally.
This method has the advantage of not messing with the country code on your phone or deleting all your preserved wi-fi connections. Of course you need to have rooted you phone and it's a bit tedious but the only other reliable method appear to be a factory reset. Bugger that.