Microsoft SQL Server contains multiple components that work together to provide data access to a variety of client applications, such as Acctivate. One of the key components for Acctivate is the SQL Server Browser Service.
The Browser Service was introduced in SQL Server 2005 as a simple way to provide SQL Server connection information to client applications on workstations. The Browser Service responds to client requests by providing a list of SQL Server Instances (e.g., ACCTIVATE) and the corresponding TCP/IP port number. The client application then re-connects to the SQL Server on the given port number.
The Browser Service listens on UDP Port 1434 on each computer running Microsoft SQL Server. You must from Acctivate workstations to the server on UDP 1434. Read our firewall exceptions article for more information.
Microsoft has an article on starting and stopping the SQL Server Browser Service. By default, the Browser Service may be disabled.
Read another article on using the SQL Server Browser Service from the Microsoft KB.