My computer says it has about 40 viruses on it and it keeps getting more and things pop up every ten seconds about it, I don't know how it got all these viruses, and now I can't go on things on my computer such as itunes and other things like that because it says its infected by viruses. But is there a way I can get rid of the viruses for free because I can't afford to purchase anything to get rid of them rite now and everything I've tried says I have to pay.

I would go to Malwarebytes.org, download their antimalware. Scan, remove the selected. Then many times you have to go back to:
Tools, Internet Options, Connections, then LAN, and be sure it is still set to Automatically Detect Settings, Click apply.
This takes care of Many.
DLL and Regestry Errors is a whole nother Ballgame.
Good Luck.
Also, go to Tools, General Tab, and then Delete, to get rid of cookies and temporary Internet Files.

The results you are seeing regarding the multiple infections are false. They are presented by a rogue which is a type of malware. Rogues download themselves to your computer then present you with astronomical results for infections. This is all a scam to get you to purchase the software. They can do considerable damage to your file system sometimes making windows inoperable at all. As the answer above notes, Malwarebytes is the best solution. I realize this topic is a little old now but if you are still experiencing these problems I will be happy to assist you. For a detailed description of the difference between malware/spyware and viruses visit my website and click on the "What is a virus..." page.