Windows 7: how can i know that my computer hits by virus

How can I know that my computer hits by virus with out any program.

Hello Alan and welcome to Seven Forums.

If I'm understanding your question, you want to know how you can tell if your computer is infected when you don't have any anti-virus program installed. I went to a couple of respected anti-virus company websites to see what they have to say:

Symptoms | Infected Computer

Computer Virus Symptoms

How To Detect Malware Infection On Your Computer | Lavasoft

And a couple of general information articles:

HowStuffWorks "How to Know if Your Computer is Infected with a Virus"

How can I tell if my computer has a virus?

How to tell if your computer is infected with spyware

How to prevent and remove viruses and other malware

Personally, if you're on the internet, there's no good reason to operate a computer without an anti-virus suite. Even if you're not connected to the internet you should still have an anti-virus suite installed. Maybe someone shares a flash drive with you and it has music or videos on it. Maybe it also contains a virus or other malware. There are so many free products to choose from. Here's a Seven Forums' thread:

What's the Best Anti-virus?

Or you can google best free antivirus products and you will find all kinds of reviews. Here's just one:

Best Free Antivirus Software

If I misunderstood your question, I sincerely apologize. If you give a bit more info about what it is you're trying to find out...

Some good options have been given to you above. Good luck with fixing your issue if you doing have a virus.

Dear marsimar. I just want to test my anti virus. I heard that there are a way to know that virus is in my computer or not. I think in run or command do that but I dont know how

Hi,

To test your anti-virus, download these EICAR test files and see if your anti-virus detects them:

Download ° EICAR - European Expert Group for IT-Security

Note : these are only test files, not actual malware.

Regards,
Golden

alan nyan what anti virus program do you have installed at this time?
Please list all.

Microsoft security essential

I'm really not sure what you mean without a program.
All anti virus programs are programs.
If your computer acts in any fashion that isn't normal it could be a indication of a infection. You would be the one to know if things are different.
If you have any doubts you can run a complete updated scan with MSE. Here are some other programs you can scan with.

Free Online Virus Scanner | ESET

Windows Defender Offline

Malwarebytes

If the post you have received don't answer your question please be more specific.
Are you having a problem?