Windows Defender alerted that my computer is affected by Trojan while Norton showed Windows Defender

Windows Defender showed an alert message that my computer is infected by Trojan and I have to register to remove the Trojan. I didn't do it. I run my Norton Security Software (not free). It did not show that Trojan infected my computer instead Windows Defender has affected my computer. Therefore, I have deleted Windows Defender from my computer and now, I think, it's okay. Yet I have to wait few more hours and see. Now, what I want to know is Why windows defender showed like that while Norton showed windows defender itself?

Windows Defender alerted that my computer is affected by Trojan while Norton showed Windows Defender.?

windows defender is not a malicious program, maybe yours was corrupted or something.

now, there's a common case that anti spyware (windows defender in your case) find a parasite and anti virus (norton) doesn't detect the same computer parasite. this happens because anti virus and anti spyware target different types of computer parasites. antivirus can't deal with spyware and anti spyware can't detect viruses, that's why both of them are needed on a single computer.

the trojan might still be on your computer even if norton doesn't detect it and everything seems to be fine. you can't be sure unless you run anti spyware.if you don't have any anti spyware besides windows defender, try spyware doctor: http://www.2-spyware.com/review-spyware-...