Harvesting x64 COM dll

[hypetsch]

Hi all,

we have Wix4 installer harvesting a 64 bit COM dll (Build with .NET framework 4.8). To do this we initially added a HarvestFiletask like this:

   <HarvestFile Include="<path-to-dll>">
      ...
   </HarvestFile>

Apparently this does not work as the required registry information is not read - the harvesting task runs the x86 heat.exe and not the x64 one.

To "fix" this we switched to the following build step in order to use the x64 heat version:

   <Exec Command="$(HeatExe64) file <path-to-dll> ..." />

Doing so the registry information seems to be harvested correctly and the COM object can be instantiated after installation. We are now just wondering if there is another/better way to accomplish this?
We found multiple similar discussions regarding 64 bit COM harvesting. Sadly non had a satisfying/working solution.

---

Just also wanted to mention that we had another issue harvesting a 64 bit type library, although not sure if it is also a 64 bit issue or related to the change from Wix 3 to Wix4. In this case the created output does not seem to be valid and results in the following errors:

error WIX0010: The TypeLib/@Language attribute was not found; it is required.
error WIX0047: The TypeLib element is non-advertised and therefore requires a parent File element. 

We back then fixed this one by manually adapting the output. Just can say that we didn't have this before switching to Wix4 which happened nearly at the same time as switching from 32 to 64 bits.