Error message when you enlist a send port that has a port filter against a user-defined property in BizTalk Server 2006 R2: "Could not enlist send port 'portname': the property specified on the filter expression does not exist"

Consider the following scenario. You enlist a send port that has a port filter against a user-defined property in Microsoft BizTalk Server 2006 R2. In this scenario, you may receive the following error message:

This problem occurs when the property that is used in the port filter has a namespace conflict with the target namespace of another schema assembly.

To resolve this problem, make sure that the namespace value on your property schema is set to a unique value. Make sure that the unique value is not used as a target namespace for schemas in other assemblies.

This behavior is by design.

For example, this problem occurs in the following scenario:

• You have two separate assemblies, such as Microsoft.Test.Schemas and Microsoft.Test.Schemas.MoreSchemas.
• The assemblies contain schemas that have similar names.
• On a send port, you specify a filter by using a Microsoft.Test.Schemas.PropertyName property.
• When you try to enlist this send port, you receive the error message that is mentioned in the "Symptoms" section.

This error occurs because the enlist process tries to load the Microsoft.Test.Schemas assembly. BizTalk Server examines the target namespace before the assembly namespace. Therefore, BizTalk finds the Microsoft.Test.Schemas.MoreSchemas assembly before the Microsoft.Test.Schemas assembly. Because the assembly property does not exist in the Microsoft.Test.Schemas.MoreSchemas assembly, you receive the error message.