5

You can achieve this using the following steps:

Add a variable i.e. User::Filename
Click on the variable, and press F4 to show the properties Tab
In the Expression use an expression similar to the following:

"C:\\Filename_" + (DT_WSTR,4)YEAR(GETDATE()) + "_" + (DT_WSTR,4)MONTH(GETDATE()) + "_" + (DT_WSTR,4)DAY(GETDATE()) + ".csv"
In the Destination Flat File Connection manager, in the expressions (found in the property tab) use this variable as a Connection String expression

@[User::Filename]