I downloaded PostgreSQL from their site - http://www.postgresql.org/download/windows
However, I can\'t create a database from pgAdmin and get a mess
Please Download from this
https://www.enterprisedb.com/downloads/postgres-postgresql-downloads
install above downloaded file
then
The solution was simply to delete %appdata%\pgAdmin (win key + r then type %appdata% got folder pgAdmin) which was created by an earlier version. On systems other than Windows, there probably is a pgAdmin directory in your user directory. Of course, all session settings etc. are gone after deleting this.