While the offline installer is safe, Windows Defender might flag any new antivirus installer as suspicious. It is best to temporarily turn off "Real-time protection" in Windows Security before running the Kaspersky installer to prevent file conflicts.

For deep system protection, the installer may ask to restart your PC. Save your work and click "Restart."

"A newer version of Kaspersky is already installed." Solution: You cannot install over a newer version. You must uninstall the current version via Control Panel > Programs and Features > Restart > Run the older offline installer.