Oracle 12 Grid installaton falsly detecting pre-existing ASM installation I seem to have run into a rather strange problem during my attempt to install Oracle 12 Grid Infrastructure:


System details: Windows2012 
Oracle 12c
Grid infrastructure for ASM (stand-alone)


I installed the grid infrastructure, but due to a network problem, it didn't finish successfully. So, I used the deinstall tool to delete it. So far so good. So, now I'm trying to rerun the install.  During the first step, if I select 'Install and configure Oracle Grid Infrastructure for a Standalone Server', I get the following error:

[INS-40404] The installer has detected a configured instance of Oracle Grid infrastructure on the server

My assumption (which may or may not be correct) is that the previous deinstall didn't clean up everything properly. 

However, if I select Upgrade Oracle Grid Infrastructure or Oracle Automatic Storage Management' I get the following:

[INS-40406] The Installer has not detected an existing Oracle Grid Infrastructure software on the system.

(Which sort of makes sense... the software was deleted.)

Anyone know how to clean this up? I've done some searching, and did find a reference to a problem under Linux where they recommended removing a file called 'ocr.loc' from /etc; however, since I'm under Windows, I'm not sure if there is anything equivalent. I've also found plenty of references to using the setup program with a "deinstall" parameter but that doesn't work either.
I think I managed to figure out the problem.

There was a registry entry under hkey_local_machine/software/oracle which needed to be removed manually. Once that was done, the install was able to proceed.