windows 10 (October 2018 update) (version 1809) deleted all my files

If you want to complain to Microsoft use the Feedback Hub app in Start Menu where developers are tasked to process consumer feedback.   But Microsoft will not even see it here because this is a  tech forums where we are mostly volunteers trying to help solve your problems.

If you still have issues then report them back in a new thread titled with the precise problem to attract someone who knows how to fix it.  This thread will soon be locked as it has run it's course.

You can try the Reset here:   Reset Your Windows 10 PC

If this is not satisfactory or won't run then do the vastly superior Clean Install following the illustrated steps in this link which include everything that works best in Windows 10:   Clean Install Windows 10 .

Make sure during the booted install to follow the illustrated steps to delete all partitions down to Unallocated Space to get it cleanest, then click Next to let it auto-create the needed partitions, format them and begin install - this makes it foolproof.

If you want to try to fix it:

If any steps cannot be performed normally then try them in Safe Mode with Networking or Safe Mode:  7 ways to boot into Safe Mode in Windows 10 | Digital Citizen

Go over this checklist to make sure the install is set up correctly, optimized for best performance, and any needed repairs get done:   Windows 10 Performance and Install Integrity Checklist - Microsoft Community

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 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.

If after all of this you still have issues then report them back in a new thread titled with the problem to attract someone who knows how to fix it.  This thread will soon be locked as it has run it's course.

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.

good luck with that I ended up having to wipe my system and go back to 1803 version. I ended up having to download and reinstall over a terabyte of software. It's a good thing I keep all of my other files like my movies and my music and my document on separate hard drives in my system. I think Microsoft should have to pay everybody whose system they screwed up and cost them data time and money. Because I will have to lay out and extra cost for the data cap I have to go over to get back everything I lost.

Update 1809 self installed October 3. I was out of the country until Oct 27th. Update roll backs can only be done within 10 days. My system was destroyed. I have ghost windows, the login camera doesn't work and issues  with Office 365. I've tried rolling back display drivers and reinstalling programs, including Office. Please provide a link to roll back this defective release. 

I have a new Surface Pro LTE

Thank you