Hi CH. I'm Greg, an installation specialist, 10 year Windows MVP, and Volunteer Guardian Moderator here to help you.
1) Here's the latest fixes working for Your Phone app:
https://www.windowscentral.com/how-fix-common-p...
https://www.guidingtech.com/fix-windows-10-your...
https://support.microsoft.com/en-us/help/405344...
https://www.groovypost.com/howto/send-sms-text-...
https://support.microsoft.com/en-ca/help/445935...
https://www.kunal-chowdhury.com/2018/08/trouble...
https://www.guidingtech.com/fix-windows-10-your...
One of these should normally fix it.
2) If not 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, and also Step 16 to test a new Local Admin account. Then continue with the other steps to go over your install most thoroughly.
3) Update your drivers and BIOS/UEFI firmware from PC or motherboard 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.
Updating drivers from the Device Manager or Windows Update is rarely enough. The most basic thing we need to learn to maintain a PC is keep the latest manufacturer's drivers installed from their Support Downloads web page.
4) If this was caused by Windows Update(s) then you can check which were installed at Settings>Update & Security>Windows Update under Update History, then uninstall them from the link there, and immediately check for these again and hide with the Hide Updates tool explained here:
https://www.howtogeek.com/223864/how-to-uninsta...
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...
5) If nothing else works then do a Repair Install, by installing Media Creation Tool and then choosing to Upgrade Now. This reinstalls Windows while keeping files, programs and most settings in place, and is also the most stable method to advance to the latest version.
http://windows.microsoft.com/en-us/windows-10/m...
If you want you can wait a week for the new version to be released into Media Creation Tool which will do the Repair Install while bringing you up to the latest version by the most stable method.
I hope this helps. Feel free to ask back any questions and keep me posted. I will keep working with you until it's resolved.
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Standard Disclaimer: There are links to non-Microsoft websites. The pages appear to be providing accurate, safe information. Watch out for ads on the sites that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the sites before you decide to download and install it.
