If permissions are not set properly in the Applications folder, Avira Antivirus for Mac cannot load several plugins. Therefore, please use the Disk Utility to analyze and fix this issue.
Note
This solution does not work on OS X 10.11
If you receive one of the following error messages, please proceed as described bellow.
1. Open Disk Utility and click Macintosh HD.
2. Click Verify Disk Permissions.
3. Click Repair Disk Permissions.
Your problem is solved if the function Verify Disk Permissions displays a sentence like:
"Permissions differ on “Applications”; should be drwxrwxr-x ; they are drwxrwxr-- .".