SSIS, Cannot map variable

I have about 8 variables that I want to export to a text file along with data from a table. After I created the derived column for each I can map all but one of them to the text file. The one the I cannot map has an expression to handle a date and convert it to a string while the others are all constants. Any ideas as to why I cannot map this variable with the expression?

"1"+RIGHT((DT_STR, 4, 1252) DATEPART("yy" , GETDATE()),2) + RIGHT("0" + (DT_STR, 2, 1252) DATEPART("mm" , GETDATE()), 2)


It would probably help if you included what is actually happening - how is it not working? Do you get an error - or are you not getting specified values - something else?

I don't see anything wrong with the expression...

Have you tried create a variable and then using the variable in the derived column transformation?