It's fairly common for malicious or otherwise obnoxious programs to hide a reinstall order somewhere. A "full manual uninstall" may require you to remove files that are not obviously associated with the program and to remove Registry entries that call up the reinstallation.

How complex this gets depends on the particular piece of s**t that's gotten to you. Generally, it's best to have complete step-by-step instructions printed and laid out where you can check off each step as you do it, especially if you're not experienced in disassembling/reassembling and applying bandages to the innards of your machine setup.

With good instructions most such removals can be done by just about anyone willing to proceed carefully and follow the instructions.

John