Due to the fact that Advanced System Care contains an Antivirus + Registry Optimiser/Editor in the one program, it has never been a favorite program of mine. I find that these 2 are not suited to be in one program. Plus I do not trust any IObit programs. (Personally only)
(1) Ad-Aware is considered to be the "old school" version of Antivirus these days generally, and has been well overtaken by most other Antivirus programs or Suites, like Kaspersky, Avira, avast!, and ESET, and even the newer Norton versions.
As a rule, I find that a free vresion of the popular Antivirus programs meets the current Ad-Aware versions.
Please read the Pinned items at the top of this section, Although some are just a bit techie or even a bit dated, they contain some of the best information that you can find anywhere. BleepingComputer is not linked to any Brand or Maker, so all items are very objective in their content.
The lists of programs here are updated on a regular basis, so all details and links are quite recent..
I hope that you never allow 2 active Antivirus programs to run at the same time, as this will defeat the purpose of the program to search for infections and to do the job that it is / was designed for. You can run an active Antimalware program along with an Antivirus program in most cases, or even install Antimalware programs to act as Inactive Scanners (cleanup programs) at any time.
(2) Please read a few of the notices in the heading of this forum area to get an idea of what I mean.
Always Uninstall one Antivirus program fully if you decide to change to another brand of Antivirus -
If you wish for more detailed links, please post back and they will always be provided for you.
Regards, from a Western district Victorian -