When you "called" them (from your home phone or cell phone) they didn't yet have access to your PC. So somewhere in the process (you don't describe it) you deliberately gave them access. A firewall certainly wouldn't block any connection you initiated or allowed yourself. I wouldn't even call them "intruders" if you opened the door yourself.
Maybe tell the whole story, with sufficient details, in chronological sequence?
I have been duped before!
Today, when trying to install a Netgear Range Extender, I found a website that I thought would help me.
I called the number given for Netgear, and an overseas tech person answered and proceeded to tell me that an intruder had invaded my PC, and somehow now I would not be able to connect my range extender to my router, unless I purchased a firewall software package.
Now, I was getting the picture, $99 for 6 mos; $199 for 1 year; and $299.99 for a lifetime transferable package, and this tech person would remove this intruders code on my register.
I hung up, and listened to the caller call back several times.
Ransomware is the latest threat, and maybe the intruders in my case were using Ransomware of some sort, because I did hear a message on my PC earlier in the day about calling a number on the website I had visited to have the malware eliminated.
I turned off my PC, and took a break.
This is when I began installing my Netgear range extender, and heard the offshore tech person tell me that an intruder has compromised my register, preventing any Wi-Fi connections to be made with my PC.
You can certainly tell me that I deserve this mess, and I will accept my stupidity, BUT
Can a firewall stop intruders or ransomware from happening?
I thought that a good malware and inti-virus software package would do this.
Thanks for any advice.