Just downloaded DF 2021 official release.
I then proceeded to uninstall RC1 from Add/Remove programs in Control Panel, and I was greeted with this error

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I don't have the "DataFlex 2021 Studio 20.0.6.121 x64.msi", however I still have the RC1 install file "DataFlex 2021 Studio 20.0.6.121 RC1.exe"

I tried to re-run the RC1 installer (hoping that it would give me the options for "Add/Remove Features"/"Repair"/"Uninstall"). The RC1 installer loaded for a few seconds, then informed me that RC1 has already been installed.

Now I am stuck with RC1.
P.S. Windows 10 Pro 20H2 19042.867. I have never had any problems uninstalling all the previous Alpha and Beta versions of DF 2021.

Frank Cheng