^ as afar as I can see, the database sandeep_FunMasti does not have the use sandeep or sandeep_sandeep. Thay are for the other database. First create the users and then try again
@ suyashpandit, you should give the database username and password in the setup.... you need to enter ur x10hosting or ur hosting's username and cpanel
delete all the database and create only one database called "sandeep_funmasti"... if u are the only database user.. better dont create any database user
Its is a big co-incidence that I bought my domain on 30th November, registered on x10hosting the next day and got my MyBB forum running the same day. Moreover, I also use FileZilla as the FTP client.