SQL Server Database Engine
Only '%s' or members of db_owner can drop the anonymous agent.
You do not have sufficient permissions to drop the agent for the anonymous subscription. The login used when calling sp_dropanonymousagent (Transact-SQL) must be a member of the sysadmin fixed server role at the Distributor or db_owner fixed database role in the distribution database, or the user must be the one that initiated the first run of the agent.
Login with the appropriate credentials, and execute sp_dropanonymousagent.