I have a program that is calling ODBC API functions using PInvoke.
I'm having trouble with SQLAllocHandle.  The third parameter is
defined in C as SQLHANDLE *, where SQLHANDLE is (void *).  I can call
it successfully normally, by defining the PInvoke signature like this:

C# class library for use by VB6.0 application uses MailMessage object, runs
OK on XP development desktop, but can't "create CDONTS.NewMail object" on
the WinNT4.0 target.  Can anyone explain how to teach the target to speak
CDONTS?

I have a C# component which in turn is called by a VB dll, this VB Dll is called by an ASP page. When I step through the code everything works fine, the asp page calls, the VB DLL, I got a Break point in my VB code & from VB I directly call the compiled C# dll, the results are ...

I am attempting to navigate the shell namespace, and as such I want to store
my IShellFolder COM object in a TreeView item for later retrieval when the
user expands the node so that I can enumerate it's children.
The problem is that when I go to reference this object again (when the ...

I am creating a COM component with C#. One of the requirements of one of the
methods is to provide the DISPID of one of the public variables.
As a temporary hack, I have been setting the class to:
[ClassInterface(ClassInterfaceType.AutoDual)]

I've written a .NET assembly which is registered for COM interop. A
method on the DLL takes a string. The method looks something like
this:
public void TestFn(string str)

I am hoping to create a list of all COM components that support interface
IUPnPDeviceControl. Is there a way to determine via the registry (or some
other means) if a COM component supports a known interface? I know I could
instantiate it and then query for the interface, but that ...

I am having some issue with EnumDisplayDevices when called from C#.
When I use CharSet.Ansi (note - no unicode) for DISPLAY_DEVICE structure, I
get
0, DISPLAY1, raphics SuperSavage/IXC 1014, 1548305232,

Okay, this one may be a bit tricky...  then again, maybe not :)
In C#, I have am calling an external DLL function which includes an LPDWORD
parameter.  According to the docs, that should be marshalled as a ref int.
Ok.  But this parameter is coming from C++ code which is then going ...

I am trying to get data from CryptMsgGetParam
I have to call it twice, first to get the buffer size needed to hold the structure which I pass to Marshal.AllocCoTaskMem, then the real call giving it the buffer to fill in
Both calls succeed and I have an IntPtr supposedly containing ...

Our codebase consists of MFC code, we are now trying to incorporate .NET code and controls
We have so far taken the approach of creating wrapper classes round the existing code so we don't have to change it.
We use the managed C++ extension and this seems to work well for non-UI ...

in the last few days I've made my first few attempts at creating mixed C++
managed-unmanaged assemblies and looking aftwerwards with ILDASM at what is
visible in those assemblies from a managed point-of-view I've noticed that:
1) for each managed and unmanaged C function (not C++ ...

Sorry to crosspost, but i'm not knowing what should be the correct newsgroup
for this....
I have a web application which i want to show a windows forms user control
in my web form. (lets call this control userControl1)

I'm trying to interface C# with the AddUsersToEncryptedFile function.
That requires a list of "ENCRYPTION_CERTIFICATE"s each with a Sid and
an EFS_CERTIFICATE_BLOB.  I can get that data well enough, but after I
take the managed list of "ENCRYPTION_CERTIFICATE"s and do

We have a C#.NET app that uses an ActiveX DLL to perform some TCP/IP actions
against a quotes server.
When we run this application as a stand alone EXE, all functions work fine,
we can subscribe to the system, and receive updates from it (By way of