This field is optional when using a custom marshaler.
You can set this field to a string that supplies additional information to a custom marshaler. For example, the same marshaler can be used to provide a number of wrappers, where the cookie is used to indicate the specific wrapper.
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.