Export failing with parameter variables

I have a query which has this filter in the where clause which prompts the user at run:

start_dt >= '&&StartDate'

The query produces output to the grid fine, but the export fails, throwing these errors:

Export Wizard error processing objects, export halted.
Error parsing Export template: Object reference not set to an instance of an object.

If I replace the above date constraint with a basic inline
start_dt >= '03-Mar-2021'
it exports fine. It's only about 2k records.

The export fails with Excel and csv and I assume other (if not all) methods.

(ver: Toad Data Point

Guessing that you're using &&vars in script language against Oracle? Regardless, I don't think TDP will recognize those types of variables in its wizards or automation tasks.

Try bind variables within the SQL
" ... WHERE start_dt >= :indt ... "

Otherwise, gonna need to know the steps/details of how you're attempting the Export.

Thx. Old habits die hard. I will read up on binds. Have been using the && parametrics forever so as to do prompts but looks like prompts can happen via binds per Using Bind Variables (toadfordataanalyst.com) That article says the &&parameters aren't supported (but they are at least somewhat).