You get "Error code 64" when accessing Replisapi.dll through ISA server

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In a merge replication topology over the Internet, when you browse https://host/app_pool/replisapi.dll through an ISA server, you may receive the following error message: 

Error Code 64: Host not available


Replisapi.dll returns an HTML page that is intended just for testing purposes. The HTTP response that delivers this HTML message is not complete. The ISA server interprets this as an invalid response and closes the connection resulting in the error reported in the Symptoms section.


When testing your web synchronization topology in these environments, use https://host/app_pool/replisapi.dll?diag.

More Information

This issue does not cause any synchronization problems.

Article ID: 2481773 - Last Review: Jan 2, 2011 - Revision: 1

Microsoft SQL Server 2005 Enterprise Edition, Microsoft SQL Server 2005 Developer Edition, Microsoft SQL Server 2008 Developer, Microsoft SQL Server 2008 Enterprise, Microsoft SQL Server 2005 Standard Edition