Thank you!
I just checked it and it has been reset from the start. There is no microsoft security essentials, I need to download and install the windows updates for the first time. But then I found Windows Defender (protection against spyware and potentially unwanted software). I'm using Win7 tho? 
If your computer is running Windows 7, Windows Vista, or Windows XP u will have defender but is only antispyware not antivirus which limited its usefulness so u have to download microsoft security esssentials seperately(it's free download). With Windows 8(and of course windows 10), Microsoft smartened up and decided to expand window's defender's functionality to include virus detection and removal.So for windows 8 and windows 10 users,microsoft security essentials is replaced with the now more advanced windows defender.
Despite the benefits of Windows Defender for a windows 8 user or Microsoft security essentials in ur case since ur using windows 7, it’s important to note that both its malware protection is weak compared to the competition. If you want something simple and native, it’s perfect. If you want something more reliable and with higher security ratings, you’ll want to look at alternative security software.Unfortunately, Microsoft Security Essentials proved weak and many experts(including my own experience with the product) suggested that users replace it with a proper antimalware product That's why i recommended malwarebytes along with the antivirus.
Edited by Advaith, 28 February 2016 - 01:04 PM.