Whenever a new version of OSX comes out, some changes require action by the user to respond the new OS behavior. TeamDrive Software is not yet available in the Apple Mac App Store. This is planned for future releases. To install TeamDrive software on a Mac now there is the following setting on your Mac OS required:
1) Click Finder then Applications then System Preferences
2) Click Security & Privacy & then click the Lock icon in the bottom left of that window
3) Make sure you have the option "Allow Applications Downloaded from: Anywhere" selected and click OK, then reboot your computer. See the graphic below:
Alternatively you may use the temporary workaround:
• Hold down the "Control" key on your keyboard and click the installer package.
• Choose "Open"