macOS Big Sur requires user approval before loading any change in a third party's kernel extension and also requires a reboot of the machine to complete the upgrade/installation process.
Egnyte's kernel extension is used to serve up a fully functional file system populated with content from the cloud without the user needing to store every file that they have access to on their machine.
Approving Egnyte’s kernel extension
While upgrading or installing the Egnyte Desktop App, you may see a couple of messages titled System Extension Updated and System Extension Blocked for a system extension signed by Egnyte Inc. (similar to what is shown in the screenshot below).
If you see these messages, you will need to open System Preferences, choose Security & Privacy, and approve Egnyte's kernel extension by selecting the Allow option next to the message saying that system software from Egnyte was blocked. To do this, you will have to ensure you click the padlock icon on the bottom left of the window to allow changes.
Clicking Allow must be done via physical access to the machine. The Allow option is disabled when accessing Security & Privacy settings via remote access (e.g. through a screen share session).
Allowing kernel extensions require rebooting the Mac device. This restart is a mandatory requirement to mount the Egnyte drive.