Wondering if someone could help me once again.
I've created two controls. Was able to publish first one without a problem, when i added a second control and performed msbuild again then re-imported solution into D365 I get the following issue.

I assumed it was because it was using the same guids, or something like that so i've tried the following:
* Deleting the build directory
* Changing the guids on the proj file.
* Changing from unmanaged to managed solution export.
* Changing publisher names
Still getting same issue. I assume something is being cached, is there a way to start a fresh.