For a few days ago i have upgraded my Creo Parametric 3.0 up to 4.0. When i try to open it, it says that quality agent could not run and all crashes. I have win 10 and M020 version of Creo if it has something to do with the issue.
I just had the same issue as you after installing Creo 4.0 for the first time (0x06000012).
In my case I deinstalled the quality manager from within the downloaded folder:
1. Right click on "qualityagent_64.msi"
2. Select deinstall
Afterwards I reinstalled the the quality agent, but I had to change the directory!
1. Again right click on "qualityagent_64.msi"
2. Change directory from "C:\Program Files (x86)\PTC\Quality Agent" to the 64bit folder where the rest of Creo is installed as well.
"C:\Program Files\PTC\Quality Agent"
3. Finish installation of quality manager.
4. Start Creo and it worked.
Maybe this helps someone.