! Next to mobile data icon
• If you happen to access a network that cannot use actual mobile data, an exclamation mark (“!”) will get displayed next to mobile data icon.
• If APN is incorrectly set, such similar icon display may occur, so you will need to check: Settings > Wireless & networks > More > Cellular networks > APN APN.
• If there is no problem with the APN to your knowledge, mobile data usage may have been disabled by the service provider, so you will need to contact service provider for clarification. (i.e.: used up limit, call restricted service, etc.)