Windows Defender Vs Webroot Spysweeper

I have Windows Defender installed on my computer and it is also updated everyday and in 2 days time I also do a full scan with it. I have also installed CA antivirus which comes for free for 1 year as a trial and this software is also saying that my pc is clean without any issues. Just few hours back I came accross a Webroot spysweeper which I installed on my pc and then update it as well. When I did a full scan with the same program then it find out 4 adware and a trojan hidden in my computer. Can anyone tell me if the inbuilt Windows Defender and the antivirus that I am using is of no use if compared to Webroot spysweeper? Thanks

Well, there are many kind of antivirus, anti-spyware available in the market and those all are updated with different virus or spyware definitions. So in that case, if you can compare the database for virus definitions used by Webroot Spysweeper could be different than that of the Windows Defender and you can never tell if it is reporting false positive as well. I tried out the Webroot Spysweeper and found it very annoying. Because it simply slow down my computer and it has got many problems in it with buggy and bloated updates. On the other hand Windows Defender is a part of microsoft operating system and it provides protection in real-time. Also, instead of Webroot Spysweeper, I would rather prefer to install Malwarebytes Anti-Malware which is much safer and not so heavier in comparison.

When you run Webroot Spy Sweeper and Microsoft Windows Defender on the same computer, you may receive the following warning message from Windows Defender:
Possible Hosts File Hijack (Medium Alert)

You receive this message when the Common Ad Sites/Blocked Web Sites Shield option in Webroot Spy Sweeper is enabled. To work around this problem when you are expecting changes to the Hosts file, let the changes occur. To do this, click Ignore in the Windows Defender Warning dialog box that contains the warning message. More information can be found here - http://support.microsoft.com/kb/919290