Avast won't close on a Mac if the program freezes or crashes. In this state, the program can't run virus scans and monitor your computer in real-time to decrease the risk of malware infections. When Avast won't close or isn't performing as expected, several solutions are available to solve problems.
If Avast freezes and crashes, the program won't shut down when you try to close it. When the program crashes, it remains unresponsive. Moving the cursor over the program displays the multicolored ring, which appears when a program isn't loading or is experiencing technical difficulty.
Avast freezes and crashes if one or more of its files are either damaged, missing or experience a temporary loading problem. The problem may also occur if you're using Avast with a computer that doesn't meet the programs recommended system requirements. Avast is only compatible with Intel-based Mac OS X operating systems. An operating older than Mac OS X 10.5.x doesn't contain the drivers and system components necessary to run the program. Such systems make it difficult to load Avast files and system processes, which can lead to freezing problems.
If Avast is unresponsive, closing it the normal way won't work. Force quitting the application is the only way to shut it down. When you force quit Avast, the Mac automatically shuts down the program's processes. Because force quitting is primarily used for troubleshooting unresponsive programs, unsaved changes are lost. To force quit Avast, you need to open the "Force Quit" window from the Apple menu. The window displays a list of the currently running programs. Clicking "Avast" and selecting the "Force Quit" button automatically shuts down the program.
Tips and Recommendations
If Avast continues to freeze and remain unresponsive, uninstalling the program and reinstalling a new copy replaces damaged files with new and updated content. Installing the latest Mac OS X system updates using Software Update in the Apple menu improves performance with this security program, because updates contain the system components, drivers and software required to run Avast.