Losing Internet Connection on PC

Several days ago, more than a week, I lost my internet connection on my PC while it is working on the other device. First, I suspected that due to the age of my computer the LAN port may be damaged. I thought even before that my cable is not working properly that is why I blogged that I bought a cable tester and a USB to LAN adapter.
I have tried to check the hardware if there is any damaged at all but I could not find one unless the internal Port is corrupted, but the device is perfectly working. I have also tried to solicit advised to several friends who are familiar with computer problems and are really computer technicians. One of the option is to find out whether the PC is infected with virus.

I have tried to download several computer virus removal but they required internet connection to run properly. Avast, Avira, and AVG. It was only until I tried Microsoft Support Emergency Tool. It is program on itself and can be downloaded to another computer with an internet connection and be executed on the infected PC. It has removed a Malware called PWS:win32/fareit.gen!C.
The Microsoft Support Emergency Tool can be downloaded from the Microsoft website free of charge.

I am not an IT specialist nor a computer technician to say whether the cause of the problem is hardware or software but so far my computer works. I also downloaded an additional Malwarebytes Anti Malware and Bitdefender.

No IT specialist can boast that  there is only one anti malware or virus protection program that can guarantee free virus or malware in your computer that can remove all infectious viruses. I recommend two or three virus protection programs are needed if your computer can withstand it and also your budget. It is better to get a premium one specially if your computer is for business. For the moment I have a free version.