I've got a data flow task which has a conditional split which then leads to two different flat file destination. The thing that is puzzling me, is why do I have different 'available destination columns' in the flat file editor's mappings tab than I do in the alternative flat file editor's mapping tab.
I'm hoping this is a Newbie error, but it's had me stumped all morning.
At the bottom of the screen, is a box with the connection manager.
If you have two different flatfile destination then you should have a connection manager for each. Inside those objects is where the columns for each destination is defined. Double click them and examine the column definitions for each. They are probably different, which is why you have a different set of columns available on the mapping page for each of your destinations.