So...MANY....thing wrong with this.
1. Why did you even use Finally Fast? Everything they do with it is FREE as long as you can type something into the search bar in google.
2. I sincerely doubt that a commercial product like that would actually give you a virus, otherwise the thousands of other people who got it before you would have complained and the company would have been shut down. If you did get a virus, it was probably just coincidental.
2a.If you have any brand of Norton virus software, it probably said it was a virus even though it wasn't. Norton protects your computer by sucking all the freedom and all of the access of your programs. (IT SUCKS)
ONTO THE PHONE CONVERSATION
3. If he actually called you back and threatened you with the cops, that is such an empty threat that it is laughable. Most likely he's in a different STATE. I sincerely doubt that he would take the time (or be smart enough) to do a phone number to address lookup, and then call the cops by the department number (911 will only connect to the local police department) and then tell them "Oh No! Someone just said 'Fuck you' to me over the phone!!!!!"
3a. If you used a cell phone, it is impossible for a standard Finally Fast employee to locate you.
4. If anything you should have laughed at him and then star 69'd him over and over again.