Copying values from one table to another table - error

[HollyGraham]

I bet this is a really simple fix, but unfortunately I just cant get this to work! Where have I went wrong?

All I am doing is copying the "currentday" values from TableR into the "currentdate" field in this table.

This is part of a model I am building so I don't want to just calculate the actual current date with python as I did previous in the model incase I'm back dating the model, so the date might not be today, I just need it to copy the date as stated in TableR "currentday" field. I'm just straight forward copying values. 

Thanks in advance!

[BlakeTerhune]

I think what you mean to do is a table join. Is there a key id field in "this table" that relates to the same id field in TableR? Once you join the tables based on this id field, you can run calculate field.