Gets or sets the error message that is displayed in a Web page in place of a control that could not be successfully added to the page.
Assembly: System.Web (in System.Web.dll)
The property can be assigned a value by a developer, so that a custom error message is displayed at the point where the ErrorWebPart control is inserted into a page.Notes to Inheritors
Developers can assign a default value to the property by extending the ErrorWebPart class and, in the ErrorWebPart constructor or in an overridden EndLoadPersonalization method, assigning a default value to the property.
To require the WebPartManager control to use a custom ErrorWebPart control, you must also inherit from the WebPartManager class and override its CreateErrorWebPart method. In that method, you should assign the value of the method's errorMessage parameter to the property of your custom ErrorWebPart control, because the WebPartManager control calls this method from several other places, and usually passes in a specific error message.
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.