CopyProxy Does Not Make a Copy for Dual Interfaces

ID: Q197781

The information in this article applies to:

Microsoft BackOffice Server version 4.0
Microsoft Windows NT Server version 4.0, Terminal Server Edition

SYMPTOMS

If you call CoCopyProxy API on a proxy for a custom (automation) interface that is marshalled by the automation marshaller (Oleaut32.dll), the API will return the following error:

S_OK

However, no copy will be made.

If you build a proxy/stub .dll for the same interface and use it as the marshaller, the API CoCopyProxy() works.

CAUSE

The old code had the assumption that CreateProxy returned a valid interface parameter, which is not TRUE for automation proxies. Automation proxies return the interface pointer only after the channel is connected.

RESOLUTION

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or Windows NT Server 4.0, Terminal Server Edition. For additional information, please see the following article in the Microsoft Knowledge Base:

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

STATUS

Microsoft has confirmed this to be a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.

Keywords : NT4SP4Fix kbbug4.00 kbfix4.00.sp4
Version : WinNT:4.0
Platform : winnt
Issue type : kbbug