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CantStartSingleInstanceException Class

This exception is thrown when a subsequent instance of a single-instance application is unable to connect to the first application instance.

Namespace:  Microsoft.VisualBasic.ApplicationServices
Assembly:  Microsoft.VisualBasic (in Microsoft.VisualBasic.dll)

public class CantStartSingleInstanceException : Exception

A single-instance application differs from a normal application in that only one instance of the application can be running at a time. When a subsequent application instance starts, it attempts to contact the first instance application to pass its command-line arguments. If the first instance cannot be contacted, the CantStartSingleInstanceException is raised in the subsequent application instance. The Visual Basic Application Model does not provide any context information in the exception.

For more information, see Overview of the Visual Basic Application Model.


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0