I do repair smart phones but I am faced with the following problem. What could cause a smart phone not to connect to service provider network.

 

There is many causes , Maybe The default browser configuration is set to Wireless Application Protocol (WAP) Browser. Or, The wireless signal is turned off. Or even the internet Service Browsing is not active with the wireless service plan or the wireless service provider does not support this feature.http://btsc.webapps.blackberry.com/btsc/search.do?cmd=displayKC&docType=kc&externalId=KB11678#3