You create and apply a protection plan with "Antimalware portection" module enabled.
You notice that Acronis Active Protection service is not started. When you try to start it manually, you get this error:
Windows could not start the Acronis Active Protection service on Local computer.
Error 1053: The service did not respond to the start or control request in a timely fashion
When you try to run its executable manually (C:\Program Files\Common Files\Acronis\ActiveProtection\active_protection_service.exe), you get this error:
The procedure entry point SetDefaultDllDirectories could not be located in the dynamic link library KERNEL32.dll
Your Windows 7 does not contain new API enhancements for Windows. Acronis Active Protection uses SetDefaultDllDirectories to limit the search directories for dynamic libraries. The fix is important to prevent DLL-Hijacking.
You can check control panel or similar for installed Windows updates (Open the Start menu -> Settings -> Update & Security > Windows Update -> View update history).
Install Security Update for Windows 7 (KB3063858)