Windows Server 2008 Standard 64 bit
Installing Sql Server SP1 x64 on Sql Server 2008 , the old one, not R2...
I got the message Invoke or BeginInvoke cannot be called
Solved closing all Windows opened after launching SETUP (setup launched "run as administrator")
then at EVERY message window during install, clicked two times on the window header to maximize it...
this way the problem disappeared and the setup completed succesfully