how to solve Network not found problem in Samsung Galaxy s2? I have UK based Samsung Galaxy s2 gt-i9100 and i was using since last 2 years without any problem in india but suddenly i found it says network problem so how to solve this ?

model number - Gt-I9100
android version - 2.3.4
plz help
Manually searching for networks for your Indian Carrier under settinga>more>mobile networks should register your SIM with your network.