Hey Nabil,
does it substitute Avira or do they work together?
Bis
You only want one virus checker installed at a time or they don't work right or may not even work at all, so either Microsoft security essentials or Avira really.
Reality of any software protection is the user being careful. I like Microsoft Security Essentials because I spot when anything is not right on my computers anyway and truth is I could run without a virus checker probably 99% of the time but wouldn't advise it, so I keep the one that hassles me the less. If you are not that great on a PC (like my girlfriend) I would stick Avira or even AVG on the PC I have AVG on her laptop but I don't like all its pop-ups all the time saying it has just protected me from something I personally didn't need protection from or even would class as a problem.
Maybe have a read of this link below explains things pretty well and is atleast truthful about the software not like many sites that seem to be biased because they obviously get advertising money from the companies selling a certain virus checker.
Microsoft Security Essentials vs Avira vs avast! vs AVG: Best free anti-virus/anti-malware program for Windows [3rd Edition]:-
http://tinyurl.com/cmlg8be
http://www.flirt4free.com
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