Can I have a windows virus that I'm 'transmitting' to others?

Hi all...

My question is I think easy: Would it be possible that my macbook has a windows virus without me knowing and can that virus be "transmitted" to others when I share files through an external disk?

I had this question for some time and today a friend told me that she had a virus on her computer and she got it after she copied some files from my computer. (she has a PC and not a Mac) Is this possible at all?

Oh and if it is possible can I get rid of the virus? I have ClamXav installed and running in my Mac but I don't know if it would detect any virus that could affect windows...

Thank you

There are no true viruses for Mac OS X (not to be confused with the more general category of "Malware", which can consist of trojans, worms, adware and spyware). There are some types of malware that effects OS X, but it is very rare and none of it self-replicates.

It is theoretically possible that you could have an infected file, that while being harmless to your Mac, could harm a Windows machine if you transfer it to someone else.

Do a full scan with ClamXAV. If it doesn't find anything, then your friend probably didn't get it from you.

The viruses that affect Windows are the only viruses that exist period. ClamXAV would have detected any virus and warned you. I think your friend is fishing. Surely she runs AV software on her Windows machine as she uses the 'net? If not advise her to download Microsoft Secuity Essentials today. It is as good as any and a lot better than many.

And it is freeware to boot.

Thank you cwa107 and harryb2448 for your replies. I will run ClamXAV. Thanks!!
J.

It sounds like you have not run a scan yet with ClamXAV? You could've given her the Windows virus. This is why I also use ClamXAV to scan my system. In the past I have found that I was carrying some Windows viruses that were passed onto me from Windows users.

Whether a person believes it's the other person's job to problem to protect their own computers, I do it to try and be nice since most of the files I'm sharing are to friends and family. Even if they have antivirus software they are not always 100% effective at catching viruses. My Dad has been infected a few times even though he has antivirus software.

The nice thing about ClamXAV is that it doesn't run in the background eating up your system resources and interfering with the performance of your computer. All you need to do is every so often do a manual scan of your whole computer overnight or individual files if you suspect it might contain a virus. You can do a manual scan in the background while using your computer too. I've done it before and it doesn't use up that much of my system resources. As the others have mentioned, you are really only looking for Windows viruses.