Am I asking for trouble if I activate Windows Defender?

I’m running Windows 7, as well as a malware cleaner called Hitman Pro. But lately, Ive been getting slow response times on my Firefox browsers, which have had me rebooting the system more frequently than I would prefer. And Hitman Pro, when it runs scans, doesn’t come up with anything more threatening than the fact that I’m getting cookies from every site I visit.

Also lately, the system as begun asking me if I wish to activate Windows Defender. Somehow I got the notion that relying upon (or even using) Microsoft’s built-in tools and utilities is a bad idea.

Should I go ahead and activate it, or should I look for something more effective?


Windows defender is a decent lightweight antivirus. I would recommend it. Unlike a possibly stricter antivirus, at least defender doesn’t slow your machine down noticably or harass you with popups. As for Firefox slowdowns - upgrade your RAM and use chrome. On an old PC, ram is cheap.

Defender doesn’t handle quite the variety of threats as some other software, but you probably don’t need all the other stuff unless you do dumb things. And the ratio of threat management to system slowdown is excellent. As SamuelA says, it has minimal impact on performance.

Windows Defender is not antivirus in Windows 7. Only in 8 and 10 does it gain theses capabilities. In 7, the MS AV program is Microsoft Security Essentials.

You can generally have multiple malware programs on your computer. You don’t want multiple actively monitoring antivirus programs. In other words, you’re good to activate it.

If you are running Windows 7, Windows Defender will remove spyware, but not viruses. To detect and remove viruses, you need to download Microsoft Security Essentials. Starting with Windows 8.1, Microsoft Security Essentials is no longer required.

nm, Fear Itself said it first

Good point, I missed this was Windows 7.

If you’re still running the 2009-era Windows 7 now, yes, you are asking for trouble. And you should look for something more effective".

If you are not running any specialized software that’s Windows only, and you have an older machine, Linux might be a good bet instead of windows 7. Basic simplest procedure: Back up everything you want to keep, onto a separate external disk; download the installer for the system you want to use; burn that installer onto a USB stick or a DVD; erase your main disk; install the new system; make sure it’s working; copy your backed up material into your new home folder; have fun!

For Firefox running slow, I suggest installing an addon like Auto Tab Discard. It will discard–i.e., remove from memory–tabs that aren’t in use. I always found it was the best thing to keep Firefox from running out of memory.

That said, before that, you may want to consider Refreshing Firefox. This will reset your profile but preserve the important settings. The only real issue is that you’ll need to reinstall your addons. It basically gets rid of all the crud from over the years, and speeds a lot of stuff up.

Only then install the extension I mentioned to keep it running quick.

Finally, if you do go with Microsoft Security Essentials, as proposed above, be sure to turn off any other software that has real-time protection. It looks like HitmanPro has this feature. Be sure it is turned off. You can still do scans with it, but do not let it run in the background. If you can’t figure out how, just uninstall it.

But hopefully you can get Firefox to stop lagging without needing to do that.

I have 4GB of RAM, but I can see why new computers have more. I have been using Pale Moon and now mostly use Chrome which is much faster.