[SalesForce] Process Builder flow generates error because of validation rule

Can anyone help me please? We have a couple of Process Builder flows in place for adding a bunch of line items to an opportunity. Our Sales users are constantly hitting a meaningless error when one of these flows runs and it's because they are hitting a validation rule (for not entering required info on the opp) and the actual error comes through to me in an email but they have no idea what's going on.

Is there any way to better handle this or any workarounds that anyone can think of? I can't see a way that I can control the error message that gets displayed to the end user and I don't know how to handle them hitting a validation rule.

Any help on this is very much appreciated.

Thanks for your time.

Kind Regards,

Brian.

Best Answer

Add a validation rule on the opp.

And(
  *Criteria_for_the_flow*,
  ISBLANK(*required_field*)
)