Force GAC installation before running .NET custom action?

Question

Hi,

I'm using a VS 2008 Setup and Deployment project to deploy a mixed managed / unmanaged application. I've had trouble registering mixed-mode DLL's using the built-in registration property ("vsdraCOM" enumerated value of the "Register" property.) As a workaround, I've added a .NET custom install assembly (with a class that derives from System.Configuration.Install.Installer.) I'm certain that that class is running and a number of operations successfully install and uninstall through code in that assembly, including executing the Dll(Un)RegisterServer entry point of a number of assemblies.

However, one DLL is not successfully registering. It is the only DLL that depends on some 3rd-party redistributable assemblies that want to be installed to the GAC. I have those assemblies installed to the GAC thanks to the built-in support for that in VS 2008's setup and deployment projects, and I know that is working. I've confirmed that what is happening is that the custom action is executing before the installer executes the GAC installation.

Whew. So my question is, is there a way to force the installer to execute the GAC installation before executing the custom action? Is there a way to use the "Condition" property of the custom action to do this? If not, what's my best alternative? Capturing the registry entries from the DLL and adding them to the registry settings for the installer (don't like this because someone may add new COM servers to the class in the future)? Using .NET code to install the assembly into the GAC manually (don't know how to do that yet)?

Thanks,

Dave

Answer 1

The setup projects you can create in Visual Studio are very limited. It only allows custom actions to be scheduled at 4 points. However, MSI allows custom actions to be scheduled at any point in the process with some restrictions on what they can do.

My first solution is to stop using Visual Studio 2008 as your setup development tool. The Visual Studio team has tried to abstract away all the complexity of creating an install. However, in the process they have also taken away all the flexibility of MSI. Wix, InstallShield, or Wise are much better products for anything but simple installs. I started off using Visual Studio for our installs and it ended up being too much work. There was always one more workaround to be implemented and its side effects to be dealt with.

If you can't switch technology, then you will need to learn how to manually modify the resulting MSI file. In your case you will need to modify the InstallExecuteSequence table, http://msdn.microsoft.com/en-us/library/aa369500(VS.85).aspx. You can do this manually through Orca, http://msdn.microsoft.com/en-us/library/aa370557(VS.85).aspx or through the MSI API http://msdn.microsoft.com/en-us/library/aa372860(VS.85).aspx. Make sure to download Orca and run the validation scripts against your install. The scripts point out numerous problems that fixing will save you countless hours when deploying to customer machines.