Helping people with computers... one answer at a time.
Files cannot be checked for viruses before being downloaded, but there are precautions you can and should take.
I'd like to prevent viruses from ever reaching my machine - can I test them before they're downloaded? And if so, how?
•
In a word, no.
But there are definitely precautions you can, and should take, that will allow you to deal with downloads safely.
•
The bottom line is that a download must be on your machine (or a machine on your local network) before you can check it for viruses. So, with that in mind, follow these steps to download safely:
- Download only from sites you trust. I know this is kind of vague (how do I know what sites to trust?), but in general that means that downloads from major hardware and software vendors, major shareware site and other reputable companies. If you're not sure, Google them to see if other people are experiencing trouble with downloads from that site.
- Always download, and never run any download. For example many programs for Windows are provided as a downloadable ".EXE", or executable file. The default action for a ".EXE" file is to run it ... meaning that the program contained in the .EXE would be allowed to run and do whatever it might want. Instead, download the file to a directory on your computer first, so that you can take the next step.
- Scan the download for viruses before installing or running it. Most anti-virus packages have the ability to scan a single file, or perhaps a single directory. Use that to point at the file or the directory you've downloaded your file into, and do the scan. Make sure your anti-virus scanner's data base is up to date.. Consider an anti-spyware scan as well.
- Assuming your anti-virus software reported no problems, install, run or otherwise use the download.
- If you have reason to be paranoid, it often makes sense to re-run the anti-virus scan and the anti-spyware scan after you've installed your download.
So what if your download shows up as being infected? First, delete the copy you just downloaded immediately, so that it doesn't get run by accident. If you can, see if you can find the same download from another source - sometimes malware is present only in some of the downloads of a particular piece of software.
If you can't find a clean download - please don't fall to the temptation of installing it anyway - it's not worth the risk unless you really know what you're doing. Contact the supplier or manufacturer of whatever it is you're downloading and report the issue to them. If they're at all reputable, they'll deal with the issue quickly.
Article C2467 * November 22, 2005 « »
Leo A. Notenboom has been playing with computers since he
was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed.
After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers
to common computer and technical questions. More about Leo.
January 6, 2009 8:18 PM
Actually you can scan a file before downloading it. DrWeb is a program that scans the file at another location other than your PC. Meaning, you never have to download the file to scan it.
August 10, 2009 9:44 PM
Hi,
I would like to download graphic design software from piratebay, like Adobe Photoshop, Illustrator, InDesign, CS4 version (software from the "creative suite" from Adobe (for Windows).
From your experience, have there been major complaints about bad viruses, malware etc regarding this software on piratebay?
Can it really be scanned before downloading? I have the latest norton antivirus instaled, which I purchased from the shop just to be sure:)
Thank you and best of luck with your good work.
Cheers,
Nick
November 25, 2009 12:54 PM
Howdly Doodly! Of course you can with Dr Web.
I wish everyone a Waddly Happy Doodly Easter!
January 30, 2010 1:09 PM
Leo,
You recommend SAVing a downloaded file vs RUNning a downloaded file. I agree. Then you recommend running an AV scan on the downloaded file. Why do that when one's default AV program does a scan as part of the download? Wouldn't this be two identical scans? I do agree that post-download rescans would be beneficial if scanned with another program -- kind of like a second opinion, or applying a different type scan (Malware scan vs AV scan).
TIA, Dale....
February 20, 2011 11:05 AM
I recomend using virustotal.com because it scans using a lot of different anti-virus software
•
Comments on this entry are closed.
If you have a question, start by using the search box up at the top of the page - there's a very good chance that your question has already been answered on Ask Leo!.
If you don't find your answer, head out to http://askleo.com/ask to ask your question.