Main.xaml: Column 1 type is not supported

Hi everyone,

I’m trying to join the contents of a csv file with the contents of a worksheet (xlsx). The column I’m creating the join on is list of names in both Table1 and Table 2 and so both are Strings. However, I’m getting the error message: Column 1 type is not supported.

Can anybody give me a clue of what I should be looking for?

Thank you.

Just as an update - I’ve tried deleting the Join Data Tables activity and setting it up again. This time it works without any problem! I’m must have done something differently, but I honestly don’t know what - as far as I can tell I did exactly the same thing?
Can anyone enlighten me please as to what the issue could have been?
Thank you!