Assuming Windows 10 64-bit... Correct
Please answer each of the following [admittedly tedious] diagnostic questions in a correspondingly-numbered list in your very next reply, preferably without quoting this post:
1a. When (approx. date) did you purchase the computer? Jan 2016
1b. Did the computer come with Windows 10 preinstalled or was it a Windows 8.1 computer that came with a free upgrade to Windows 10? preinstalled
- What is the full name of your currently-installed third-party anti-virus application or security suite (i.e., not Windows Defender!), if any, and when (approx. date) does your current subscription(if any)expire? ESET NOD32, expires this year, but not for a while.
- What third-party anti-malware applications (i.e., not Windows Defender!) are installed, if any? What third-party firewall, if any? Malwarebytes, Spywareblaster
- Has a(nother) Norton application or a McAfee application EVER been installed on the computer since you bought it?
It came with it, but I never used it, or installed it. I uninstalled it as soon as I got the computer.
- The Dell computer came with a McAfee free-trial preinstalled. Have you ever run the McAfee Consumer Products Removal Tool? I don't remember if I used their removal tool, or not.
- Is KB3135173 or KB3135174 [PICK ONE] listed in Installed Updates (not Update History)? [1] 3135173
- Is Adobe Flash Player v20.0.0.306 installed? Yes
- Is Firefox (version 44.0.2 or higher) and/or Google Chrome (version 48.0.2564.116 or higher) or any other alternate browser installed? Yes
- Are you in the habit of using "registry cleaners" (e.g., CCleaner's Registry Cleaner component; Comodo System Cleaner; Advanced SystemCare; Advanced System Optimizer; Glary Utilities; McAfee QuickClean; AVG PC TuneUp; Norton Registry Cleaner; Norton PC Tuneup; PCTools Optimiser; PC Doctor; Registry Mechanic; RegCure; RegClean Pro; Registry Booster; SpeedUpMyPC; System Mechanic; TuneUp Utilities; WinMaximizer; WinSweeper; Wise Care 365; Wise Cleaner)? No. I use CCleaner, but never for a registry cleaner. I do use a registry backup program from tweaking.com though.
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[1] Control Panel | Programs and Features | View installed updates (in left-hand menu)