Additions to this Web site have been blocked - Error Message in SharePoint 2010

After Restored a site, when I tried to edit anything on the site, I received the following error message.

"Additions to this Web site have been blocked."

In both browser and Powershell console.

This is a common issue after every restore...

Possible cause
1) Site Collection Quotas is reached.
2) Site Collection is set to Read-only (blocks additions, updates, and deletions)\

Resolution:

Go to Central Administration.

Click Application Management

Click Configure Quotas and Locks

Set the Site Lock Information to "Not Lock"

Hope this help... Good luck!