We have 1.2 installed on all the office machines.
I (main Dynamo developer in the house) have upgraded to 1.3 on my computer, but I still need to maintain the old graphs.
I tried to uninstall 1.3 and re-install 1.2, but the installer refuses to install 1.2.
It tells me that I already have a newer version installed, so it won’t install Dynamo Core.
I have run the Windows uninstaller and manually deleted every “1.3” folder I could find, but I still can’t install 1.2.
There are FAR too many registry entries to manually delete.
Is there any way I can downgrade?
(And, no, I can’t just use 1.3. Some of the packages have changed and nodes have been deprecated & are unavailable)
We have 160 installations, so upgrading the entire office won’t happen for a while, either. Especially not until I fix everything that broke in 1.3
That’s what I did.
well shoot. Maybe reinstall 1.3 and use IOBit Uninstall Utility. It does really clean uninstalls
Great tip, John! Thanks:+1:
IOBit didn’t quite fix the problem, but at least it identified it.
Turn out it wasn’t 1.3
IOBit showed me there was a 1.2.1 Dynamo Core installed, and I was running the 1.2.0 installer.
So, yes, a newer version. Just not the newer one I assumed.
No idea why 1.2.1 didn’t show in the Windows Control Panel uninstall, though.
Not only that, but even IOBit couldn’t clean it completely. I had IOBit uninstall and even delete registry entries and I still couldn’t install 1.2.0.
Finally ran the 1.2.2 installer and it was happy.
No wonder my brain hurts this week.
At least in is Friday and National Donut Day 
Worked for me!
Revit 2019 and Dynamo was awful at this time!
downgraded to 2018!
5/23/2018