Tungsten Search and Matching Server – No databases available
When trying to create a new Tungsten Search and Matching Server Database with SQL Server, there are instances where the database name drop-down list will be blank.

This is due to the fact that the user account used to connect (SQL user or service acocunt) does not have read access to query data from sys.master_files view.
The solution is to request the customer to grant us read access to query data from sys.master_files view, as KSMS will execute the below query to get the list of databases.