DSXchange

When checking operator: A sequential operator cannot preserve the partitioning
of the parallel data set on input port 0.

In the stage immeadiately prior to the sequential stage set Preserve Partioning to 'Clear' - this is on the Stage tab, under Advanced.

Are you telling us or asking us? If you are asking us then, do a search on "sequential operator cannot preserve the partitioning".

Oops, I knew the answer and went steaming in there - yeah, do a search.