During a complete fresh installation I choosed a case sensitive password with an "!" inside the string, it works fine for the normal login, but when I try to use sudo or su or passwd or some GUI stuff which requires a password I get an authentication error.
I really have no idea what to do, I tried to enter the password in an editor to check numlock, etc... no problem.
After the login I get an error (ca. 1 minute after login), in german:
"Es wurde ein Problem mit einer Systemanwendung festgestellt"
Something like:
"There is a problem with a system process/program"
