Ambiguous reference error in Visual Studio .NET

Last Published: April 25, 2020

Error Message

When more than one ArcWeb Service is referenced in Visual Studio .NET, the following error may occur:

"Ambiguous reference"


.NET returns an error if more than one Web service share the same object, even if that object is placed separately into every Web service namespace. For example, Geometry is an object shared between many ArcWeb services.

Solution or Workaround

Give a full namespace path when declaring the object.

For example, a declaration for a point object would be:



MyApplication is the name of your project


AddressFinder is the alias for the Web reference that points to the Address Finder Web Service WSDL.

Article ID:000005798

  • Legacy Products

Get help from ArcGIS experts

Contact technical support

Download the Esri Support App

Go to download options

Related Information

Discover more on this topic