While creating a site column which uses metadata you may come across the error ‘The default termstore for this site cannot be identified’.
To solve this issue open Central Admin and go to the Manager Service Applications.
In the list search for your Managed Metadata Service.
Select the Managed Metadata Service Connection and click on Properties which is located in the Ribbon.
For you to use this feature in your site columns you need to have a default location to store column metadata. Check ‘This service application is the default storage location for column specific term sets.’
You can now create the custom terms for your column.