If you have anti-virus program installed on your PC, you can verify if it is working properly or not simply by using the EICAR virus test.
The EICAR virus test is a HARMLESS text file that you can create by yourself to test your anti-virus and its been detected as a virus by most Antivirus vendors without causing any damage to your PC.
The file was provided by EICAR, which stands for European Institute for Computer Antivirus Research.
Describes below is how to carry out the test:
1. Open Notepad and paste the below string into it . X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H*
2. Save it with the name fakevirus in any of your folder/drives or on your desktop and as soon as you do, your antivirus real time protection should be able to detect it.
3. If this file got deleted immediately...then it means that your antivirus is working properly and updated !!
4. If this doesn't happens and you see the saved file in that folder, RIGHT CLICK the file and select SCAN with your installed antivirus and if the scan shows the file then it means your antivirus is working properly BUT not updated with a new version, as best antivirus softwares detect any virus (at the same second when you save the same in your system) without your effort of going to specified folder and scanning the folder.
5. If it doesn't shows any kind of threats, then you need to change your antivirus software immediately with a better one with the latest update.
How did your anivirus react after saving the test file ?