Assuming Win7 64-bit...
Please answer each of the following [admittedly tedious] diagnostic questions in a correspondingly-numbered list in your very next reply, preferably
without quoting my post:
1a. When (approx. date) did you purchase the computer?
1b. Who manufactured the computer (e.g., Toshiba; HP; Dell; Lenovo)?
1c. Have you ever done a Repair Install and/or a clean install of Windows 7?
1d. Has Win10 ever been installed on the system?
2. What is the full name of your installed anti-virus application or security suite and
when (approx. date) does your current subscription expire? What anti-spyware applications (other than Defender) are installed? What third-party firewall (if any)?
3. Has a(nother) Norton application or a McAfee application EVER been installed on the computer
since you bought it?
4. Have you ever run the Norton Removal Tool and/or the
McAfee Consumer Products Removal Tool?
5. Is KB4041681 and/or KB4040980 listed in Installed Updates
(not Update History)? [1]
6. Assuming Java is still installed for some reason => Is Java Version 8 Update 151 (or higher) installed? TEST HERE USING INTERNET EXPLORER ONLY! =>
http://java.com/en/download/uninstallapplet.jsp [2]
7. Is Adobe Flash Player v27.0.170 installed and if not, can you get it installed? TEST HERE USING INTERNET EXPLORER
ONLY! => https://helpx.adobe.com/flash-player.html
8a. When (exact date) was Internet Explorer 11 installed according to
Installed Updates?
8b. Was IE11 "just" offered & installed via Windows Update or did you have to install it manually?
8c. Were you running IE8, IE9, or IE10 before you installed IE11?
8d. What Update Version & KB number are displayed in the second line of text in IE11's Help | About [Alt+H+A] tab; e.g.,
Update Version: 11.0.99 (KB1231231) ?
9. Is Firefox version 56.0.1 (or higher) and/or Google Chrome version 62.0.3202.62 (or higher) or any other alternate browser installed?
10. Are you in the habit of using "Registry cleaners" (e.g., Registry Mechanic;
System Mechanic; RegCure; RegClean Pro; Advanced SystemCare; Total System Care; Glary Utilities; Registry Booster;
McAfee QuickClean; AVG Quick Clean; AVG PC TuneUp; Norton Registry Cleaner;
Norton PC Tuneup; PCTools Optimiser; SpeedUpMyPC; FixMyPC; PC Doctor; TuneUp Utilities; WinMaximizer; WinSweeper; Comodo System Cleaner; Advanced System Optimizer; CCleaner
Registry Cleaner component)?
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[1] Start | Control Panel | Programs and Features | View installed updates (in left-hand menu)
[2] No need to install Java if it's not already installed!