Run multiple antivirus applications on one PC

Fred langa By Fred Langa

Conventional wisdom says antivirus tools don’t work well together — so a PC should have just one tool installed at any time.

In most cases, that wisdom is still correct — but if you pick the right kind of software, there are ways to clean a PC with multiple AV tools.

Is it OK to piggyback AV applications?

Reader Steve Mutchler wants to use a custom suite of antivirus apps to thoroughly scrub a PC free of malware. But he’s not sure how to do it.
  • “I do a lot of virus cleaning for home users. For the most part, I slave a user’s hard drive to my computer and run my various AV tools on it.

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    “I would like to have two or maybe three AV engines installed on my PC at the same time so I can run all three of them one at a time, because I think we all agree that no AV engine is 100%.

    “But AV tools don’t play nice together. For example, running Sophos and Webroot together, or Norton with most anything else, locks the computer up tight. Any thoughts on this subject?”
Full-time AV apps don’t work well together because each one integrates tightly with the Windows operation system. Having multiple AV tools simultaneously hooked into the OS — intercepting calls to disk drives, networking subsystems, and other system components — can cause major problems. In some cases, as Steve says, it’ll lock Windows up.

Disabling an AV tool’s top-level, user-controllable elements is not enough. Its low-level components remain in place — in some cases, still active and still able to interfere with other AV software you might install.

The solution, Steve, is to use AV tools that are not meant for full-time use. When you need additional cleaning, I suggest you try one or more of the free online scanners — tools specifically designed to search and clean systems that may be infected. More or less standalone, they don’t need to hook deeply into your OS.

I use these AV scanners:
  • Microsoft’s OneCare Safety scanner (info page)
  • Eset’s Online Scanner (info page)
  • TrendMicro’s HouseCall Free Online Virus Scan (info page)
I’d be remiss if I stopped here, Steve. I think you need more protection than AV tools alone provide — you’re plugging a known-infected disk into your system!

At a minimum, minimize any interaction between your PC and the infected disk. For example, disable any apps on your system that automatically maintain a disk index — search tools (Windows Search, Google Desktop, etc.), photo album tools (Picasa, etc.), and so on. If you leave them running, they may discover the new drive and access its files to index what’s there. That may be enough to infect your host PC.

And I’d go one step further. Set up a virtual PC (VPC) with networking disabled and no shared drives. Do all the disinfecting from this isolated, virtual system. If any malware gets loose, it’ll remain trapped inside the VPC.

For more on virtual PCs, see my Dec. 17, 2009, item, “New virtual-PC software outshines Microsoft’s.”

This is a long answer to your question, Steve, but you’re doing something potentially hazardous to your PC, so it’s important to play it safe.

It’s also important to reiterate that, in most cases, running two or more full-time AV tools is bad idea.

But there are exceptions to every rule. The standalone scanners listed above work fine alongside standard AV tools.

Organizing Win7’s Start menu is quick and easy

Don Lachot is having trouble getting his Start menu to work the way he wants it to.
  • “Windows 7 doesn’t seem to allow me to organize programs by right-clicking on the start button and selecting, as I was able to do before. How do I, for example, cut Adobe Reader from the main start menu and place it into the accessories menu?”
Drag and drop! It’s as simple as that. Using your example, click Start (within an administrator-level account), All Programs, then Accessories. This will open the Accessories folder tree in the left pane.

Now scroll upward until you see the Adobe Reader icon. Click and drag the icon to an empty spot between the items in the Accessories folder. (See Figure 1.)

click-drag items where you want them
Figure 1. To customize your Start Menu in Win7 and Vista (in an Admin-level account) simply click and drag items to a new spot.

Release the mouse button, and the Reader icon should drop into the location you selected. (See Figure 2.)

rearranging is easy
Figure 2. It takes only a few seconds to rearrange items as you wish.

You can also return an item to its original location with the same technique.

My new computer has too much RAM?

In all the years I’ve covered personal computers, I’ve never, ever, had a letter like this one from Donald Friend:
  • “I recently purchased a new computer with a 64-bit processor and 12GB of memory. The problem is that the computer never uses more than 2GB. A memory monitor never goes above 20%. Could you do an article on configuring Windows 7 to maximize the use of all available memory?”
Twelve gigs of RAM? Wow!

I hope this doesn’t disappoint you, Donald. I think your system is operating fine — you simply have way more RAM than you currently require.

The amount of RAM you need at any given moment is determined by the software you’re running. You say your memory monitor typically shows around 2GB of RAM in use. That sounds about right for a normal mix of consumer software.

For comparison, I’m writing this column on a 32-bit Win7 notebook with 4GB of RAM. It’s a normal workday, and I’m currently running 12 apps (including two browsers with a total of 9 tabs open) and 37 major processes. I’m using 1.4GB of RAM, roughly the same ballpark as you. (Remember that 64-bit code itself takes somewhat more memory space than 32-bit; that alone could account for much of the variance in our respective systems’ memory use.)

In both our systems, unused RAM is available on an as-needed basis, to be employed only when we run software requiring more memory. If your system needs only around 2GB of RAM to accomplish your normal tasks, there’s no easy way — or particular benefit — to try to make those same tasks use more RAM than they really need.

But you can use the “extra” RAM for new tasks. For example, you could set aside about 6GB of RAM for a RAM drive. This won’t do much for routine operations, but disk-based operations run much faster on a RAM drive than they do on spinning platters.

For example, while writing to CDs or DVDs, most burning apps use a buffer to cache the data. Putting the buffer on a RAM drive should speed up the copy portion of the operation. has a good article, “How to make a RAM drive in Win7 64.” It may spark ideas on how to use your fallow RAM. Just remember that a RAM drive goes away when the PC is shut down — it’s not for longer-term storage.

Beyond that, there’s not much you can do to modify the amount of RAM your setup actively requires. Use 64-bit apps where you can, and they’ll automatically use as much of your abundant RAM as they need. (For more on 32- vs. 64-bit computing, see “Choosing between 32- or 64-bit Windows,” in my March 18 column.)

By the way: Someone might tell you to set your pagefile (or swapfile) to the smallest-possible size, forcing Windows to use more RAM to run itself and your apps. However, with Vista and Win7, doing so could lead to instabilities and crashes, according to some online reports. (If you try this, back up your system!)

It will probably be many years before most of us will need 12GB of RAM for normal PC tasks. So think of it this way, Donald: you’re way ahead of the curve!

Freeware alternative to BCDedit

Vista and Win7 ship with BCDedit, one of the system utilities I discussed in my April 1 item, “Tools for managing Win7 and Vista system bootup.”

Thomas Rose found a nice alternative to BCDedit:
  • “I’ve found this tool to be useful: EasyBCD is NeoSmart Technologies’ 100%-free, Vista bootloader modification tool.”
Like Microsoft’s app, Softpedia’s EasyBCD (download page) is free. Unlike the Microsoft tool, EasyBCD has a pleasing graphical front end — and it can edit the boot records of other operating systems besides Windows.

Thank you, Thomas. Choice is good — and even better when it’s free!

Have more info on this subject? Post your tip in the WS Columns forum.

Reader Thomas Rose will receive a gift certificate for a book, CD, or DVD of his choice for sending the tip we printed. Send us your tips via the Windows Secrets contact page.

Fred Langa is a senior editor of the Windows Secrets Newsletter. He was formerly editor of Byte Magazine (1987–91), editorial director of CMP Media (1991–97), and editor of the LangaList e-mail newsletter from its origin in 1997 until its merger with Windows Secrets in November 2006.
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Fred Langa

About Fred Langa

Fred Langa is senior editor. His LangaList Newsletter merged with Windows Secrets on Nov. 16, 2006. Prior to that, Fred was editor of Byte Magazine (1987 to 1991) and editorial director of CMP Media (1991 to 1996), overseeing Windows Magazine and others.