Sounds very much like the rogueware/scareware attacks
that have been around since the early 00s
This site lists 349 by the end of 2007
http://www.spywarewarrior.com/rogue_anti-spyware.htm
The different types of the malicious explained
https://www.bleepingcomputer.com/vir...ams-scareware/
The tactic is very simple - scare the novice IT user into thinking their infected
and have no choice but to buy help via the phone number
Sadly this still works on a small percentage of the population
More likely than any malware infection you might find the hosts file now has some
unblocked bad servers / sites which you'll be sent to when searching.
Small program like rkill should tell you if anything has been changed in windows
https://www.bleepingcomputer.com/download/windows/
rkill explained - read before using because it does have conflicts with some software
https://www.bleepingcomputer.com/for...o-the-program/
As prevention is better than playing junior detective
How to Harden Your Browser Against Malware and Privacy Concerns
Covers most of the usual browsers
http://www.techsupportalert.com/cont...y-concerns.htm