We recently upgraded to 4.7.16 and immediately starting having problems when checking for duplicate records.
I set up a very basic merging test -- same last name and email, I've tried picking a very small group (100 contacts), and I always get the same error.
No matter what Matching Rule or whatever group I create (even if it has a couple contacts), I always get the error.
My technical skills are very limited, so I was just checking to see if anyone else has experienced this.
Thanks!