Hey Ben. I'm Greg, an installation specialist and 9 year Windows MVP, here to help you.
Try these steps for whichever is involved: Mouse or Touchpad, as this could be the problem.
Try another mouse in this PC to confirm if Windows is the problem.
Access the Device Manager reached by right clicking the Start button, choose the Mouse/Touchpad, then Driver tab. First try Update this Driver > Automatically, then Roll Back if available. If not choose Uninstall button, restart PC using keyboard to Ctrl Alt Del, on blue screen tab to Power Icon in bottom right, press Enter, arrow down to Restart, press Enter to restart to reinstall the driver.
Adjust the Touchpad and mouse settings in Settings > Devices > Mouse/Touchpad checking all settings including the Additonal Mouse Options box - check Settings on all tabs.
Report back all results for possible other things to try.
To check if Windows is causing this you can also 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.
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.
If this was caused by Windows Update(s) then you can check which were installed at Settings>Update & Security>Windows Update under Installed Updates, then uninstall them from the link there, and hide with the Hide Updates tool downloaded from here: http://download.microsoft.com/download/f/2/2/f2...
You can also use System Restore to get before the problem began, then check for Updates with the Hide Update tool and hide them: http://home.bt.com/tech-gadgets/computing/how-t...
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...
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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