Apple Mail says its Offline

Problem

When using the Apple Mail application, it keeps saying that it is offline and you are unable to send messages as a result.

Solution

Mac OS X 10.8

1. If Mail is open, press cmd + Q to quit the application.
2. Click on the Finder icon in your dock
3. Press cmd+shift+G

4. Copy and Paste this address into the pop up
   ~/Library/Containers/com.apple.mail/Data/Library/Preferences

5. Delete the “com.apple.mail.plist” file.

You can then try opening Mail again.

Mac OS X 10.7 and below

1. If Mail is open, press cmd + Q to quit the application.
2. Go to your home folder.
3. Go to the Library folder.
4. Go to the Preferences folder.
5. Delete the “com.apple.mail.plist” file.

You can then try opening Mail again.