Unable to create a database. Check that your hosting account has at least one database available. If it does, please contact your host.
how many databases do you have exactly? Have you heard of database normalisation? Or are you creating a single database for each individual client........ wrong!
Either optimise your database (singular, not plural) or upgrade for more data allowance.
If you don't have even one database and are getting this problem, please either be more specific as to the type of website you have, in order to get a specific answer, or contact support.