I really hate to resurrect this post.... but... I am going too.
I am trying on one system to go from 2019.1 inventor to 2019.3 without installing 2019.2 first. Reason being is I am just trying to test and gather set steps (that will work) in order to update some of our systems for testing. I have walked through and done all the steps indicated in our previous posts. Even the ones I have personally confirmed worked when 2019.2 came out. But copy design is failing miserably and after trying everything I can't get it to work. Windows 7, Inventor 2019.3, vault 2019.1.1, I did the adp core.dll fix, reg hack, and copied additional files as well as reboot, run as admin (inventor, vault, and inventor view), etc... more than once. This was yesterday. Was hoping today it would magically fix it! Wasn't so lucky. Running Vault Basic. This nasty message that seems to haunt us has been the one showing up again.

I checked the value of the current version in the registry to make sure it was pointed to 2019 inventor and it was.
The only thing I can think of is on this machine is I did not update to 2019.2, I went from 2019.1 to 2019.3. The machine I initially tested this work around on I went from 2019.1, to 2019.2 (did the patch fix) then updated to 2019.3. Do you think that could be my issue? Is there some other registry setting or something I can check to make sure the system forces to re-register? I never did get that message and before doing all of this I was working in 2018 for a while. So it very well could be that, I just don't know how to check any more than checking the current version path stored in the registry and the fact when I open up files through windows explorer it does open up in inventor 2019 (not my normal practice). Everything I think I could check in terms of re-registering it seems to all be pointing to 2019. But I could be missing something. Open to any more ideas. Thanks.
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