"Error occurred while running Database Configuration Assistant" (doing a clean reinstall of Oracle)

Symptom: Oracle installer gets almost to the end then says "Error occurred while running Database Configuration Assistant".

Possible causes:

• Bad download/media
• Not clean install
• Oracle services are still on the PC
• The computer name contains a number at the end.

Solution:

• Ensure that the computer name does not begin with a number.  If it does, change it before proceeding.
• Ensure that "AccessData Oracle" is not listed in Add/Remove Programs or Programs and Features.  If it is listed, uninstall it.
• In the registry (regedit) navigate to HKLM\System\CurrentControlSet\Services and delete all keys that start with the word "Oracle".  Also delete the HKLM\Software\Oracle key, then reboot.
• Delete the "Oracle" folder from the root of the drive that you specified as Oracle's install path (eg. if you installed Oracle on C:\, delete the folder "C:\Oracle").
• Delete the "Program Files\Oracle" folder.
• Mount/burn the Database installer and install Oracle.