Whilst setting up a Linked-Server connection from SQL-2012 to Oracle the installation of “Instant client for Windows x64” failed.
To clean-up the mess left I downloaded the ‘Oracle Deinstall Tool’ from http://www.oracle.com/technetwork/database/enterprise-edition/downloads/index.html by clicking ‘see all’ next to Windows x64 within the Oracle 11g2 section.
To use the tool, I opened a command-prompt on my windows-server and changed directory to the folder containing ‘deinstall.bat’ from the above download. The command that worked for me was “deinstall -home D:\Oracle\Client_64”.
BTW@ The path-part of the deinstall command (above) was the ‘Oracle_Home’ location. There are a bunch of ways to find that. I looked in the Oracle Universal-installer.
Finally, I tidied-up my local (enviroment?) Path, by cutting/ pasting from/ into the ‘path’ command – to remove all traces of Oracle.