My answer obviously will not answer your question but I will try to explain why it is useless attempt:
This - "I don't want to create more than one user account to solve this." is the most common error. No one educated administrator would work on computer under administrator's account. It used only for administrative tasks, such as program installations or adjusting settings for the whole computer.
If there only one account, it is means it is administrator's account and if somebody has access to it then he/she can revert all of your restriction attempts. It isn't applied to a real humans only, but it applies to a viruses too. If they runs under administrator account, - it isn't your computer anymore.