There are multiple posts about this. We cannot support Avogadro 1.2 anymore. If you want to install the missing DLL, you can find instructions here
But my suggestion would be to use the latest beta from Install — Avogadro 1.100.0 documentation
There are multiple posts about this. We cannot support Avogadro 1.2 anymore. If you want to install the missing DLL, you can find instructions here
But my suggestion would be to use the latest beta from Install — Avogadro 1.100.0 documentation