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How to Scan for Viruses and Spyware – for Free!

Maliscious websites attempt to add malware to computers.

Maliscious websites attempt to add malware to computers.

One of the most common questions I get is how to scan a computer for viruses and spyware if there isn’t an up-to-date antivirus package installed. As most of you know by now an out of date antivirus program is all but useless.

Almost exclusively, I use McAfee’s SuperDAT scanner to clean up systems that I suspect are infected. This handy little package is updated extremely frequently and as such is really useful on a computer where there’s no updated security package running.

First you will obviously need to download the SuperDAT package. Click the link above, agree to their terms of service, and then download the SuperDAT package. It’ll be called something like sdat5195.exe (that’s what it is as of the time of this writing). Save the file to somewhere that you’ll be able to locate it. I would suggest c:temp as we need to expand the file you just downloaded; it’s an auto-extractor.

Once the file is downloaded click Start->Run and browse for the file. Before you click OK to run the file, you need to put -e on the end of the command line. This instructs the package to extract itself into the directory the file is currently in, as opposed to trying to update some installed McAfee software suite.

The command line should look like this:


Now it’s time to scan your computer. First, to ensure that we have minimal interference, boot into Safe Mode. Once fully booted there, click Start->Run once again and type CMD. This will open the command prompt and is where all of the action will take place. You didn’t expect it to be easy since it’s free, did you? :)

Assuming that you saved it to C:Temp as I suggested, here is exactly what you’ll need to type to run this:


CD Temp

Scan /adl /unzip /clean /rpterr /report c:temperror.txt

Here is an example of what it’ll look like running from the command line:

McAfee scanner running from the Command Prompt

McAfee scanner running from the Command Prompt

Here’s a breakdown of what all the switches mean:

/ADL = All Drives Local: The scanner will go through all of your physical drives, skipping the removable ones (CD-ROMS, Floppies, Flash drives, etc)

/UNZIP = Extract all archives: If a file is in a compressible format that the scanner recognizes, then it will scan within that archive. This way viruses that may be hiding in a compressed file are found.

/RPTERR = Report all errors: Any errors that are encountered will be included in the file you designate under the /REPORT flag.

/REPORT = Generate a report that will list all viruses found and save it to the path specified. In this case it was C:TempError.txt.

If you want to look through the other flags that you can use, then type Scan /? . It’ll bring up a list of the other possible options that you can use.

If you run into a few files that don’t allow themselves to be cleaned even while booted to Safe Mode then you may want to try using Barts PE to scan your machine. It boots independently of your computer’s OS and as such no files on your hard drive are in use, which will allow you to clean up pretty much anything. You can use McAfee’s SuperDAT in conjunction with Barts.

If you need a simpler solution, I suggest you check out Windows PC Repair by Reimage.  Their claim to fame is their ability to repair your PC without having to reinstall Windows.  They repair or replace damaged Windows files and restore your PC back to its full performance level.

About Kevin Souter

Kevin Souter is a full time computer technician and operates a computer repair site, as well as a free spyware removal site. http://www.tweaksforgeeks.com has articles and tutorials on all sorts of computer problems from internet issues to hardware defects, for the novice and the expert.
  • Mckinley

    Thanks for the guidance enabling me to uproot the trojan. The use of normal English throughout, and with no acronyms, or assumed interfacing skills enabled me to shuttle between minimizing your instructions and minimizing my pages of execution and simply do it step by step. I have system mechanic pro but it couldn’t deal with those bugs.

  • Jason

    Thank you so much!!! I have an old Norton antivirus and it wasn’t cleaning my computer of the virus that my grandson got on it but your instructions helped me get rid of it! Thanks again!

    • http://errortools.com/ sammeh

      Hey. TotalSystemCare is a utility software you can use for fixing just about any computer issue that you might have, including malware. You can download the utility tool here. … http://errortools.com/
      All the best

  • Micha

    Hi, I’ve got an HP laptop that keeps getting the Trojan-Downloader-zlob virus. It is sending data to some ip address that I think is in Moscow. Norton and Spybot: Search and Destroy haven’t taken care of it. I don’t have internet right now on the computer because I don’t want it sending information to that addess so I tried to use Norton to get rid of it but it won’t. Can you help?

  • Sootah

    Since you’ve disconnected your computer’s internet connection, I have to assume that you’re not running your Norton antivirus with it’s latest definitions.

    If you don’t feel comfortable hooking your machine back up to the ‘net, then you can download the sdat mentioned in the article above to a flash drive from another computer and then copy it to your machine.

    Trend Micro also has a command line scanner, although you’ll have to update its virus signatures manually.


    As always, run the scan(s) from safe mode for them to be the most effective.

  • Adam Bevan

    Many thanks for very clear instruction on how to get a error log and virus removal from mcafee superdat.

    If possible it would be great to know what to do next. I could not find any information in your piece on how you eliminate spyware. many thanks, Adam Bevan

  • Oscar

    I tryed your steps to get remove all the addware and was unsucsessful i have a hidden window running i found the file and unable to delete it is says it running i tryed in safe also it stillsayes it can not be deleted because it is running please help i did all the scans with your recomended softwareit found it but says it running in safe modeand cannot delet the path is windows/systems32/awvvs.dll please help

  • sindhu

    My system got infected with Worm Win32 Netsky.Its keep giving strange pop ups and opening websites.Please help to remove it.It has changed my default page also

  • http://www.tweaksforgeeks.com/how-to-scan-for-viruses-and-spyware-for-free/ Daniel

    my system is infected with Worm.Win32.netsky. at least thats what the pop-ups are telling me. the pop ups keep sending me to fake sites trying to sell me fake spyware removers. it has also hijact my browser and opens webpages unannounced. im running windowsxp prof. with updated McAfee Security Center along with SpyHunter3 and i also used McAfee’s SuperDAT. they all come back with the same result.
    No corrupted files or folders
    Summary report on C:*.*
    Total files: ……….. 184674
    Clean: …………….. 184388
    Not scanned: ……….. 0
    Possibly Infected: ….. 0
    Cleaned: …………… 0
    Non-critical Error(s): 3
    Master Boot Record(s): ……… 1
    Possibly Infected: ….. 0
    Boot Sector(s): ……………. 1
    Possibly Infected: ….. 0
    and i still keep getting these anoying pop-ups.
    Do you have anything else to kill this thing?

  • Sootah

    Another nice scanner – although it won’t remove anything by default is Panda’s ActiveScan which is part of their new Infected or Not campaign.

    This scanner is kept extremely up to date courtesy of their revamped platform, so it may detect viruses that other scanners miss.

  • Hannah

    I tried this is in suggestion from the cant download anything well my computer wont download the scanner??? I really am at a loss I cant get anything that would scan my computer?

  • Nuz

    Hello I am sure this would work if only my laptop would allow me to even allow this download. I have checked my internet settings, checked the firewall which is on but I am not confident enough to work without it on.
    I tried to download CCleaning, as well as what you recommend above and have had no joy.

    I am scratching my brain in vain and I have exhausted the online advise as well.

    How can I even start to fix this problem if it won’t allow anything to be downloaded. I even went as far as trying to do a system restore and that didn’t work either.