installing-a-wia-error-handling-driver-extension.md

title	description	ms.date
Installing a WIA Error Handling Driver Extension	Installing a WIA Error Handling Driver Extension	04/20/2017

Installing a WIA Error Handling Driver Extension

The error handling extension should be installed together with the WIA driver. In order to install the driver's error handler together with the driver, a small number of additions must be done to the driver's INF file.

The following example shows how an existing driver INF file can be modified to include the error handler.

MyDriver.AddReg]
...
HKCR,CLSID\{UiClassId}\shellex\ErrorHandler\{ErrorHandlerCLSID}
...
HKCR,CLSID\{ErrorHandlerCLSID },,,"My Error Handler"
HKCR,CLSID\{ErrorHandlerCLSID }\InProcServer32,,,%11%\myerrhandler.dll
HKCR,CLSID\{ErrorHandlerCLSID }\InProcServer32,ThreadingModel,,"Both"
...

[MyDriver.CopyFiles]
...
myerrhandler.dll
...

[SourceDisksFiles.x86]
...
myerrhandler.dll=1
...

The {UiClassId} class ID is the value that the driver returns for the WIA_DIP_UI_CLSID property and {ErrorHandlerCLSID} is the class ID of the error handler. In this example, myerrhandler.dll contains the implementation of the error handler.

The first entry in the AddReg section is to register the error handler as a WIA extension for the driver. The following three entries register the error handler as a COM component.

The ThreadingModel value for the error handling extension must be Both.