I am having the same trouble after recently upgrading to Big Sur. Apologies I can only reply in English. macOS 11.4 Outlook 16.51 Kaspersky Endpoint Security for Mac 11.1.0.210aWhile Kaspersky is running, Outlook uses 100% CPU and a constant stream of the following messages appear in Console. When stopping Kaspersky by doing the following, utilisation drops back to normal levels. sudo launchctl unload /Library/LaunchDaemons/com.kaspersky.kav.kavd.plist && sudo launchctl unload /Library/LaunchDaemons/com.kaspersky.klnagent.plist && sudo launchctl unload /Library/LaunchDaemons/com.kaspersky.sysextctrld.plist Upon restarting Kaspersky, CPU utilisation hits 100% again after a few minutes. Uninstalling and reinstalling KES did not fix the problem. Disabling protection in KES preferences did not fix the problem either.