[Verizon HTC 10 Questions & Answers] REtails:
I am assuming you used Sunshine to S-OFF your device. If so, it should be relatively simple to fully restore your phone to stock, just be sure to perform the following steps in order.

Please note that I am in absolutely no way responsible for any damage done to your device as a result of following these instructions. Do not proceed to read the following post or attempt to perform the procedure described below if you do not accept this agreement. I am not responsible for your actions in any manner!

note: all commands are to be entered without quotation or ' ' marks

-Flash a full stock Verizon RUU zip over your current setup to clear any modified flags, unroot, etc. Links and instructions are available in this thread.

**WARNING** It is critically important that you verify that the RUU ("OS") install was successful. I would run a factory reset from the stock recovery AFTER installing the RUU to ensure that you do not encounter any boot loops before proceeding as going S-ON with a borked rom makes for a quick brick. Please heed this precaution seriously! VZW TEC "insurance" plan or similar coverage in case of brick highly recommended! **

-The only way to get back to "Locked" is to run Sunshine again and choose the "S-OFF LOCKED" option that is now available, however you cannot run Sunshine without going back S-ON first. Install the latest Sunshine.apk now, your license should be restored automatically.

-Once you are sure your RUU has completed installing and successfully booted all the way up, connect your phone to your PC with USB Debugging Enabled.

-Download Android Debug Bridge and install to an easy to type directory such as 'c:\adb\'.

-Open a new command prompt (run cmd.exe) and navigate to your adb directory, ie: 'cd c:\adb\' .

-Issue the command 'adb devices' to check that your phone is connected properly and detected by adb, you should see a device identifier come after a short delay.

-Now we must go S-ON so that Sunshine can be run again. Issue the command 'adb reboot-bootloader' and manually enter download mode.

-Once the phone has booted into download mode issue into the command 'fastboot devices' to verify that your phone is detected by the fastboot utility.

-To go back to S-ON, issue the command 'fastboot oem writesecureflag 3' (NO TYPOS!!). The prompt should confirm success at which point you can issue 'fastboot reboot'.

**Boot issues?**->If the phone fails to boot, factory reset through stock menus.

Assuming all is up and running, run Sunshine, and select "S-OFF LOCKED' this time around.

-Once that process is done, use the prompt to reboot back into the bootloader and then enter download mode. All that we have to do is S-ON and we are S-ON Locked!

-Issue 'fastboot oem writesecureflag 3' and once successful, reboot with fastboot.

**Boot issues?**->Lastly factory reset again if data partition read issues soft brick the phone again via the stock menus, I do not believe this will be necessary but it is not a big deal if it turns out to be.

Voila~ You are now S-ON Locked and should not have any tamper flags if you ran the RUU immediately prior to the S-ON process!

Please let me know if you have any questions here or via PM and please do not do anything you are not sure of!! You run a substantial chance of bricking by messing up while reverting to stock! There are tons of resources around here to reference too! Hope this helps~

Edit: anti-liability level +5000 lol