ActiveX DLLs must be registered with regsvr32.exe on each computer where it is used. The regsvr32.exe is a Microsoft program that is present on all Windows systems (from Windows 95 on up). The purpose of regsvr32 (in a nutshell) is to create registry entries so that ActiveX objects may be instantiated by name. For example:
set objInstance = CreateObject("Chilkat.Xml")
When the DLL is registered with regsvr32, there is a registry entry that points to the filesystem location of the DLL, thus allowing the DLL to be loaded into memory and used. Here is more information about ActiveX registration and regsvr32.
Most setup / deployment / installer tools and programs automatically recognize ActiveX DLLs when added to a project, and make the proper adjustments so that the DLLs are registered with regsvr32 when your application is installed. (Note: Microsoft provides functions that are equivalent to regsvr32 in the Platform SDK. This is how setup/deployment/installer tools typically register an ActiveX. The Platform SDK function name is DllRegisterServer.)
If your installer program does not automatically register DLLs, check to see if there are property settings per file that can be changed.
The Chilkat ActiveX components themselves are distributed using the Microsoft Visual Studio’s Setup and Deployment functionality. The install package produced is a ".msi". Visual Studio’s Setup and Deployment projects automatically recognize ActiveX DLLs and register them during deployment. (Note: Not all DLLs are ActiveX’s. The Chilkat .NET DLL is a .NET assembly, which is NOT an ActiveX and therefore does not need registration via regsvr32.)
Deploying a Chilkat ActiveX with your Application
The purpose of the .msi you downloaded from Chilkat is to (essentially) display a license agreement, copy the DLL onto your computer, and register it with regsvr32. All Chilkat component licenses allow for royalty-free redistribution of the Chilkat DLLs with your application. Therefore, you should locate and add the Chilkat DLL(s) directly to your application’s setup/deployment project. It is not necessary for your end-customer to download and install the Chilkat .msi separately.