Error 1618 when installing any software on Windows
You can find this error during for example Skype or Java Runtime Environment installation. And probably many more. It just means that another program’s installation is in progress and current one can’t continue.
It happens in most case, when you try to install some software, when Windows Update is installing heavy portion of updates. And current program can’t install or update some system elements, that are being updated by Windows Update in the same time.
Solution? Wait some time (until end of Windows Update process?) and then restart installer of your program.