Elliott's answer below appeared to be correct.

Have you tried dropping the subscribers from the publisher first, and clear the following tables in the database on the subscriber, then recreate the subscription?

sysmergearticles

sysmergepublications

sysmergeschemachange

sysmergesubscriptions

Did you set up alias on the publisher or subscriber? I ran into the same issue too. And did you have to stop and restart the SQL server...