Ok, I took all of my attachments off and the error went away.  Added one back and it was back.  My attachments are mostly for form 8949.  But I also have some K-1 attachments.  In the efile attachment area I list them all as Other, with the form and schedule number in the description area.  This is the first return I have tried to file this year with attachments so it seems like there is a problem with any attachment.