Had installed 3.0 and tried to uninstall it and got error saying Win64 not supported so I installed 3.01 over top with no problem but I tried uninstalling to see if I got the error and I did. I did not have problems removing version 2. This started with 3.0.
I had the same problem (Win 7 64 Prof).
The uninstaller is a Java Applet. It has got a bug. If you have both Java 32 & Java 64 (Win XP 64 / Vista 64 / Win 7 64) the uninstaller tries to use JAVA 64 --> The Win 64 error message.
Workaround: Uninstall all Java 64 versions and let only Java 32 on your machine.
Uninstall Intel Toolbox --> Works without Problem.
Then you can install Java 64 an the Intel Toolbox.