Try the steps recommended below.
Check to see if you’re signed with a temporary profile
Go to Settings > Account > Sync your settings;
If you are signed in with a temporary profile, you’ll see a message "You are logged on with a temporary profile. Roaming options are currently unavailable."
This means that the system is trying to attach an extra account to yours, you’ll need to restart PC and sign in again to get your account settings and data back.
You can directly use Search to search for your files. If you don’t see, use the troubleshooter to fix the problems with Search: open Search and type: indexing > Indexing Options > Advanced > Troubleshoot search and indexing. Then you can try to find files in Search again.
If the files are hidden, you may follow below to find hidden files in Windows 10:
In the search, enter Show hidden files and folders > Select Show hidden files, folders and drives under Hidden files and folders;
Try the search again; If you need to find a certain type of files, type: *.doc or *.mp3 etc to search.
If you have created a backup before Windows 10 update, you can restore the backup and find lost files back:
Type: Backup and restore in the search > Open it and select Restore my files; Then follow the instructions.
You can also recover a file by creating a new one with the same name and file type;
After creating the new file, right-click it and select Properties > Previous versions and pick the file to restore.
Keep me posted for further assistance.
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