iMessage says “Waiting for activation…” error; how to fix

Several users have reported that they are unable to use iMessage because they could not activate it. This short article explains how to troubleshoot iMessage activation issues on iOS devices (iPad, iPhone and iPod touch).

Please note that activation may take up to 24 hours to complete. Leave iMessage enabled for 24 hours. Do not toggle iMessage off and on during this 24 hour. After 24 hours, if you are still having this problem; try these:

• Update your device to the latest iOS version
• Toggle off and on iMessage
• Make sure that you have an active Internet connection
• Tap  Settings > General > Date & Time, make sure that Set Automatically is on and make sure that correct time zone is displayed.
• If possible, try to connect to another Wi-Fi
• Reset your network settings by tapping Settings > General > Reset > Reset Network Settings
• Restart your device
• Tap Settings > Mail, Contacts, Calendars > My Info and select yourself from the list

If above tips do not help, please try the following (!extreme solution):

• Disable iMessage (Settings > Messages) and  back up your device (iTunes or iCloud) (related: How to back up your iOS device) and tap Settings > General > Reset and select “Erase all content and settings”. This will delete everything. When iOS setup assistant start, select “Set Up as New iPhone”. Sign in to your Apple ID with iMessage and then restore your device from your backup.

Related:

• iOS6: Messages (iMessage) not working, How to fix
  
• iOS 5: iMessage not working – how to fix