Locked Application

The application logo has a small silver lock on it.

The small silver padlock shows that the system lock bit is set. This lock bit can be set or unset in the "General" brick of the "Get Info" panel. For some applications this lock button is dimmed. Then you can only disable it from the Terminal.

In that case, use these steps:

1. Open Terminal (/Applications/Utilities).
2. Type this, followed by a space: sudo chflags -R nouchg
3. Drag the application you would like to unlock into the Terminal window.
4. Press Return.
5. Check the commend you entered carefully for typos, before proceeding.
6. Enter your password and press Return.

Silly question, but have you clicked on the little padlock in the lower right corner of the "Sharing and Permissions" brick and authorized as administrator? Your screenshot is still showing the locked padlock.