Hi Joan. I'm Greg, an installation specialist and 9 year Windows MVP, here to help you.
You can take it back and ask for one that actually works, or contact the manufacturer's Support which is included free in the first year as this may be a known issue.
Can you get into Safe Mode with Networking, or Safe Mode: https://www.digitalcitizen.life/4-ways-boot-saf...? If so:
Update your drivers from the PC maker's Support Downloads web page, using the full model number, Serial Number or Dell Service Tag on sticker. Compare the latest drivers available for download with the ones presently installed in Device Manager reached by right clicking the Start Menu. Make sure you have the latest BIOS or UEFI firmware, Chipset, Display (Video), Sound, USB3, Bluetooth, Network and all other drivers, or else download and install the latest now.
Go over this checklist to make sure the install is set up correctly, optimized for best performance, and any needed repairs get done: http://answers.microsoft.com/en-us/windows/wiki...
Start with Step 4 to turn off Startup freeloaders which can conflict and cause issues, then Step 7 to check for infection the most thorough way, then step 10 to check for damaged System Files. Then continue with the other steps to go over your install most thoroughly.
If nothing else helps you can run a Repair Install by installing the Media Creation Tool and choosing from it to Upgrade Now. This reinstalls Windows in about an hour while saving your files, apps and most settings, solves many problems while also bringing it up to the latest version which you need anyway and by the most stable method. http://windows.microsoft.com/en-us/windows-10/m...
You can check now if Version 1803 is installed at Settings > System > About and if not skip to the Repair Install which is the most stable way to Upgrade to it anyway and will repair most problems. But Repair Install cannot be run in Safe Mode, which brings me to:
But remember that in Windows 10 everything depends upon the quality of the install, and Factory or Upgrade installs are inferior installs which most enthusiasts won't even run because they'd expect endless issues. Consider now or later doing the Clean Install in this link which compiles the best possible install that will stay that way as long as you stick with the tools and methods given: http://answers.microsoft.com/en-us/windows/wiki...
There is also an automated Fresh Start that reinstalls WIndows while shedding corrupting factory bloatware, saves your files, but doesn't clear the drive to get it cleanest: https://www.howtogeek.com/265054/how-to-easily-...
I hope this helps. Feel free to ask back any questions and let us know how it goes. I will keep working with you until it's resolved.
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