How does one 'Extract Com Information' from an OCX without InstallShield?

Question

In one of the projects our team is working on, we are trying to make an automated deployment system for an existing desktop application. In order to do that we need to understand how InstallShield installs the application to begin with.

We have access to the InstallShield manifest, but there is an OCX file that we cannot figure out how to install manually (without InstallShield). This particular OCX file is set to 'Extract COM Information'.

Here's a screenshot:

The other OCXs in this application are self-registering, so they can be registered with Regsvr32.exe. But the OCX we are having problems with cannot be registered in that fashion.

How would one manually install an OCX file that is set to 'Extract COM Information' in an InstallShield manifest?

Answer 1

RegSvr32.exe calls the LoadLibrary API to load your DLL and then invokes the DllRegisterServer entry point inside your DLL. The code inside that function does the actual COM registration. If RegSvr32 is failing, that typically means a dependency of your DLL is missing or invalid.

InstallShield does all of this along with some really low level bit hacking to virtualize all of this and then harvest it. An old article on the subject is:

Spying on Registry Entries

InstallShield doesn't actually use this technique per say ( they have several techniques, most of which is not documented and various filters and transform engines to clean up the data ). If you are just looking for a way to do it without InstallShield, then look at Windows Installer XML's "Heat" command line tool. This can "harvest" COM metadata into WxS XML elements.

Also WiX is open source so if you are really curious you could go looking at their code.