I believe it was release 16 in which Rockwell changed how date and time are referenced. Our distributor has failed to renew our techconnect contract, and things like changes to how we read and write the date and time are apparently too specialized for r.a. to release to everyone in their knowledgebase.
If memory serves me, we had to change some of ours from DateTime to LocalDateTime as the attribute after upgrading to v16.
If you give us more specifics, about the details of the instruction which generates the error, I am sure you'll get a quick solution.