Alert: Attention macOS High Sierra Users: We are aware there may be some compatibility issues between macOS High Sierra and Mozy. Your backed up data remains protected. We will continue to provide updates as they become available.
Does the error give any other details? This sounds like a Microsoft/Windows error and not a Mozy specific error, and so I just googled it and it looks like it may have something to do with permissions on your user account (for the computer), are you installing it under the Administrator with full privileges? Mozy does require that it be installed under the Admin account on the computer and that you allow it administrator and system privileges to run properly.