Error need help(net.Frameworks

Ok i keep getting a freaking error thats pissing me it keeps poppin up it says "Unhandled exception has ocurred in your application. If you click continue, the application will ignore this error and attempt to close. If you click quit the application will close immediately." and then below it says "Mailbox unabavilbe the server respone was 5.4.5 daily sending quota exceeded. 7sm522059yxg.68." anyone know y this is happing or how to fix it?

Reinstall .NET Framework, man.

well i didnt reinstall it but it stopped doing it but ill reinstall it