This error is caused by the absence of the Maxiguard.dll file in your client. Your virus scanner or Windows Defender may have detected MaxiGuard.dll in the client as a threat and deleted it. There is no malicious software in any DLL or exe file in the Rollet client. Add an exclusion to the game folder from your Windows Defender or virus scanner.
Click here --> Download Maxiguard.DLL Then, you can resolve the error by extracting the rar file and inserting it into your client.