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SqlConnectionStringBuilder.UserInstance Property

Gets or sets a value that indicates whether to redirect the connection from the default SQL Server Express instance to a runtime-initiated instance running under the account of the caller.

Namespace:  System.Data.SqlClient
Assembly:  System.Data (in System.Data.dll)

public bool UserInstance { get; set; }

Property Value

Type: System.Boolean
The value of the UserInstance property, or False if none has been supplied.


To set the value to null, use Value.

This property corresponds to the "User Instance" key within the connection string.


This feature is available only with the SQL Server 2005 Express Edition. For more information on user instances, see Connecting to SQL Server Express User Instances (ADO.NET) and "User Instances for Non-Administrators" in SQL Server Books Online.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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