Column "A" cannot convert between unicode and non-unicode string data types

I am following the SSIS overview video-
https://secure.cbtnuggets.com/it-training-videos/series/microsoft-sql-server-2008-business-development/6143?autostart=true
I have a flat file that i want to import the contents onto a SQL database.
I created a Dataflow task, source file and oledb destination.
I am getting the folliwung error -
"column "A" cannot convert between unicode and non-unicode string data types"
in the origin file the data type is coming as string[DT_STR] and in the destination object it is coming as "Unicode string [DT_WSTR]"
I used a data conversion object in between, dosent works very well
Please help what to do