Hi @mingliang93,
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I grasp that while you were working, your computer started to upgrade to Windows 10. You did not initiate the upgrade when an error occurred and it started reverting the changes back to Windows 8.1. You then got a restoration incomplete error with three options showing.(Save Log, Details, Retry). You chose retry but the same menu options reappeared.
As it could not complete the restoration. You could try the troubleshooting option in the HP Recovery Manager. If that does not help or you are unable to utilize this function, I suggest you do a recovery back to factory settings. HP PCs - Performing an HP system recovery (Windows 8). Should you need recovery media and you did not create yours. please contact HP Support to obtain a recovery kit. Contact HP Support. During the recovery, there is an option to backup your personal files to prevent data loss. Should you select that option, here is a link to help you with restoring your files. HP PCs - Restoring Files that were Backed Up Using HP Recovery Manager (Windows 8).
Should you like to prevent this from occurring again here is a link to assist you. Any ads on the page are not endorsed or recommended by HP. How to prevent Windows 10 upgrade files from downloading automatically on your PC (from windowscentral.com)
Please let me know the outcome.
Thanks for being a part of the HP community. Please let me know if this helps resolve the issue by marking this post as "Accept as Solution". If you require further assistance, let me know and I will gladly do all I can to help. If you wish to say "thanks" for my efforts, click the "Thumbs Up" to give me a Kudos.