In most cases your computer will run very slowly once the anti virus program has been installed. If you have an older computer internet security suites usually will be very heavy. I use a 7 year old computer that only has half a gig of ram so even though it has a decent CPU it lacks the ram to run such programs. I recommend avast if your computer has a heavy anti virus program installed. Make sure you delete the old anti virus program.
By using Antivirus
antivirus
Mcafee
Yes, but I'd feel safer using it with antivirus.
If your antivirus software is unable to quarantine a detected virus, it is either because of A) An error was encountered while moving the virus to quarantine on the hard disk, or B) The virus is putting up a fight against your antivirus software. When this happens, delete the virus or send it to the developer of the antivirus software if possible for analysis.
Antivirus software can be defined as a program that works to detect and remove harmful viruses from a computer. Antivirus software combats computer crime by shielding one's personal information and essentially their identity, online.
Get yourself a good antivirus.
you use antivirus and scan the computer then remove the virus
Antivirus software will notice about the virus,malware,spyware etc
"antivirus" is protective software designed to defend your computer against malicious software.
It's essential to have antivirus for your computer because it will stop virus from infecting your computer. I recommend AVG, here's a link to its download: free.avg.com/us-en/free-antivirus-download
Get an antivirus software.