Cannot execute sp_dropmergearticle if the publication has a Subscriber that is running on a version of SQL Server 2000 or ...

Cannot execute sp_dropmergearticle if the publication has a Subscriber that is running on a version of SQL Server 2000 or earlier. Drop and re-create the publication without the article '%1!s!' or set the publication compatibility level of publication '%2!s!' to '90RTM' before calling sp_dropmergearticle.