I first installed PortableApp Plateform on a sd card. But later I decided to install the whole thing on a usb key. Perfect. No problem. But it's just merely impossible to uninstall the portableApp Platform from my former sd card. Tried format, a simple erase, an partition erase and... PortableApp appear again like a charm. Just incredible.
Have you got an answer to that great mystery?
You should just be able to erase the PortableApps.com folder from the SD card. Have you tried that?
The two most important days of your life are the day you are born and the day you find out why.