If you find the string in a log file without any accompanying crash, freeze, or error code, you can safely ignore it. The trouble begins only when Checked 4 is the or when it appears thousands of times (creating a log flood).
Set the executable to run in compatibility mode for Windows XP (Service Pack 2 or 3) by right-clicking the file, selecting Properties , and navigating to the Compatibility tab. Cep21reg.exe - Checked 4
It is used to unlock the full version of the software by entering a registration name and serial number. If you find the string in a log
The "Checked 4" checkpoint validates registry entries for extensions. Corrupted registry keys often lock the process. or error code