What to do when getting INS-30606: Partially cleaned ASM home is found.

Today I was trying to install the new Oracle database 11.2.0.3 software on an existing RAC cluster - for upgrade.

However on the Grid Installation Options screen I found that I couldn't press Next because every time an alert window stating "INS-30606: Partially cleaned ASM home is found." would pop up during verification checks.

I am not running ASM - instead I am using NFS for all my data, OCR and voting files. Also, I had just removed the OLD Grid Infrastructure ORACLE_HOME (11.2.0.2, which I have just upgraded to 11.2.0.3) using the de-installer from: http://download.oracle.com/otn/linux/oracle11g/R2/linux.x64_11203_deinstall.zip. This ORACLE_HOME turned out to be the culprit.

After playing with the oraInventory inventory.xml file etc. I finally noticed that on both nodes the following line had previously been added:

+ASM1:/u01/app/11.2.0/grid:N           # line added by Agent
+ASM2:/u01/app/11.2.0/grid:N           # line added by Agent

Commenting out or removing this line from both nodes fixed the problem and the Oracle Installer would allow me to continue (no need to shutdown the installer).