You cannot update Avast without this

Instup.exe is an executable file that is downloaded along with other files when you install Avast antivirus software on your computer. It is a very important part of the virus scanning software. Without instup.exe, you may not be able to update Avast on your computer. Despite being a legitimate file, instup.exe is known to cause performance issues on Windows devices.

For example, some Avast users report that instup.exe sometimes consumes up to 100% of CPU resources, rendering other apps unusable. If that describes your situation, we'll show you how to fix it and prevent the file from impacting your PC's performance.

“Avast Antivirus Installer” is the official file description of the program file instup.exe. When you install Avast Antivirus on your computer, instup.exe makes sure everything runs smoothly. And there’s more: the executable also keeps Avast up to date with the latest virus definitions on your device.