Hi Sonalik,
the file "#sqlbb4_..._0.MYI" is a temporary file. Did your server or mysql - server crashed and left this file undeleted?
Can you confirm, that you have enough disk space left on "C:\" ?
To see what "Errcode 22" means, pls. use the command line an type "perror 22".
Are all necessary Plesk services active and running?