Avast is an assortment of award winning, high-end tools that work in ideal synergy. To protect your system and precious data against computer viruses is the only goal of the Avast antivirus. It represent as a top-notch solution for every window-based computer.

Avast antivirus uses Virus definitions (VPS) to detect malware and other threats on your PC, that why it is so essential to ensure the update Virus Definitions on regular basis. The user-interface and all components which are present in the Avast antivirus are referred as applications. For bug fixes or some general improvement, application needs to be updated usually.
By default, both Virus definitions (VPS) and application are automatically updated whenever a new version is available. But, if you want to update both of them manually, then you need to visit www.avast.com/support on your web browser. For this, you can also follow the below mentioned instructions.
Instructions to manually update Virus definitions (VPS):
• After Right-clicking the Avast icon select Update and then go to Engine and virus definitions.
• Tap on Check for Updates.
• After the update is complete, you will be notified that “Virus definitions are up to date”.
• Hit “Restart Now” to reboot directly, if you’re asked for it.
Method to manually update the application:
• Right-click on the Avast icon to select Update and then choose Program.
• Simply tap on check for updates, if Avast doesn't begin to check for updates.
• Avast will automatically download update and notify you after the application become up-to-date.
• Click on the “Restart now” button to reboot your PC immediately.

By applying the following methods or instructions, you can easily update VPS and application of Avast. Due to less knowledge of computer or not able to understand above methods, if you can’t update both VPS and application, then you need to make a call at Avast Customer Support number and take help from highly experienced professionals.