>>>>Hi again Naomi,
>>>>
>>>>how do I use this function in a computed field now? I've added the field to the table and put GetDatePaidTo(PolicyHeaderPK) as the formula but it tells me "Error validating the formula for the column" when I try to save the table definition.
>>>
>>>
>>>Looks like I need to enter it like this:
>>>
>>>([dbo].[GetDatePaidTo]([PolicyHeaderPK]))
>>
>>Yes, for functions you always need to specify the schema.
>
>It was more than just the schema, the brackets/parentheses are apparently also necessary

I don't think so. You can type without brackets, SSMS designer will convert to brackets by itself.