When you implement a custom marshaler in a Microsoft .NET Framework 2.0 application, an exception is not raised to the managed caller. The exception should be thrown at the ICustomMarshaler.CleanUpNativeData method to indicate an error in native code.

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next Microsoft .NET Framework 2.0 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

Microsoft .NET Framework 2.0, 32-bit systems

Microsoft .NET Framework 2.0, 64-bit systems

Microsoft .NET Framework 2.0, itanium-based systems

To work around this problem, set the in/out attribute to the parameter that you will perform custom marshaling on. After you have set the in/out parameter, call the MarshalNativeToManaged method after the native method is called. Your custom marshaling call must resemble the following:Note On a computer that is running a 64-bit version of Microsoft Windows, you can work around this problem by using only this workaround. However, on a computer that is running a 32-bit version of Windows, you must apply the hotfix package before you use this workaround.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information, click the following article number to view the article in the Microsoft Knowledge Base: For more information, visit the following Microsoft Developer Network (MSDN) Web sites: