As mentioned by Henk and RichM, this may help solve your problem. If the problem persists, you may have to consider a factory reset on your Wi-Fi router or Cable Modem/Wi-Fi router combo device as well. There are now new viruses that infect these devices, and they are very hard to get rid of! The best way to do so, is to disconnect
ALL of your wireless as well as wired-devices from the Wi-Fi router/Cable Modem-router combo unit, and perform the factory reset per the manufacturer's instructions. After the reset is done, reconnect only 1 device at a time to your router/modem and check for proper operation. Once the 1st computer is connected (a wired connected computer is best to use first if you have one) and working properly, add in the 2nd computer and test, if ok, add the 3rd computer, etc. etc.
NOTE: If you have a Cable Modem-router combo box or DSL Modem-router combo box, as Charter, Cox, and Verizon are now regularly using, it's best to contact them and have one of their Tech's walk you through this procedure. Many of the ISP providers have complete control over those boxes, and you cannot have access to them, as they either own them outright, or lease to you. Factory resetting these boxes can inadvertently shutoff your Internet due to something we call "provisioning", which checks your equipment's electronics for proper authorization to use the Internet from your location. If the reset is performed and you lose your provision on that box, you're Internet may no longer work.
If you have an older setup, for example you have 2 boxes; one that your Internet provider gave to you when you 1st had your Internet installed (may have been put in by your ISP installer or Tech), and the 2nd box could be a Wi-Fi router or a Wired Router that you purchased in a retail store like Staples or Best Buy or online. In this case
DO NOT RESET THE CABLE MODEM OR DSL MODEM; only do the factory reset on the Wi-Fi router or Wired Router that you purchased!
If you do the reset on the 2nd box as per the above paragraph, and your problem persists, you may have a very stubborn virus and it may still be lurking on one or more of your PCs on your home network.
In this case, more drastic measures are required. If this occurs, it might be wise to employ the services of a licensed network engineer and pay him to sort this problem out for you. If you decide to proceed, the first step is to
MAKE A COMPLETE BACKUP OF ALL PERSONAL DATA TO EXTERNAL MEDIA first on each and every computer on your home network. From there, you may be looking at doing complete windows reinstallations on all connected computers, as well as replacing your 2nd box router (wireless-router or wired-router).
Hopefully you don't have this problem, but it's been occurring more frequently here to my Customer's home computer networks, so this is why I mention it.
Good luck,
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