How to Solve "Auto Backup Stalled" Error in Your Phone

"Auto Backup Stalled. 3 Days Since Last Backup"

Since a few days ago, I've been getting this error message on my phone. That was very annoying. So I Googled a little, and found the cause and a solution.

This is caused by the photo backup feature in Google+ app in my phone. This occurs if you enable Auto-Backup and disable Auto-Sync.

So the simple solution is to either enable or disable the both of them. You can do that at 

Menu > Settings > Auto Backup

Hope this will be helpful to someone.