Fix "User Profile Service Failed the Sign-In" in Windows 11

The Problem

"The User Profile Service service failed the sign-in. User profile cannot be loaded." appears after you enter your password and stops you at the sign-in screen. The account exists and the password is right — Windows simply cannot open the profile behind it.

Windows keeps a list of every profile in the registry, with a path to the matching folder in C:\Users. Sign-in fails when that record and the folder disagree: the entry has been marked as a backup with a .bak suffix, the path points somewhere that no longer exists, or the profile status flags say the last load did not finish. That happens after an unexpected shutdown, a disk that filled up mid-login, an antivirus quarantining part of the profile, or a failed update.

Your files are almost always still there, sitting in C:\Users\<yourname>. This is a broken pointer, not a deletion.

Getting in but with an empty desktop and a warning about a temporary profile instead? Closely related, different fix — see fix "signed in with a temporary profile".

Symptoms

• "The User Profile Service service failed the sign-in" after entering the correct password.
• One account fails while other accounts on the same PC sign in normally.
• Started after a forced shutdown, a full disk, a Windows update, or an antivirus scan.
• C:\Users may contain both yourname and yourname.000 or TEMP.

Step 1: Restart and Free Up Disk Space

The simplest causes first — a genuinely full system drive prevents a profile loading at all.

1. Restart the PC properly rather than powering it off. If you can only reach the sign-in screen, use the power icon in the bottom-right → Restart.
2. Sign in to any other working account, or the built-in administrator, and check free space: Settings → System → Storage.
3. Anything under about 10 GB free on C: is likely the cause. Clear space: free up disk space when the C drive is full.
4. Try the failing account again before doing anything more invasive.

Step 2: Get In Using Safe Mode or Another Admin Account

You need a working session to make the repair.

1. If another administrator account works, sign in there.
2. Otherwise use Safe Mode: hold Shift while clicking Restart on the sign-in screen → Troubleshoot → Advanced options → Startup Settings → Restart → press 4.
3. Full routes: how to enter Safe Mode in Windows 11.
4. If you have no other admin account and Safe Mode still fails, go to Step 6 and work from the recovery environment.

Step 3: Repair the Profile Entry in the Registry

This is the fix that resolves most cases. Take the backup in the first sub-step — registry edits are easy to get wrong.

1. Windows + R → regedit → Enter. In Registry Editor, select File → Export, save a full backup, and keep it somewhere you can reach.
2. Navigate to:

   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
   

3. Click each S-1-5-21-… subkey and read ProfileImagePath on the right until you find the one ending in your username.
4. If you see two keys for the same user — one plain and one ending .bak:
   • Rename the plain key by adding .temp to the end.
   • Rename the .bak key to remove .bak.
   • Rename the .temp key to end in .bak.
   • You have now swapped them: the good profile record is live again.
5. If you see only one key, work with that one.
6. In the now-live key, double-click State and set its value data to 0. If a RefCount value exists, set it to 0 as well.
7. Confirm ProfileImagePath points at the real folder, for example C:\Users\ankit. Correct it if it points at a .000 or TEMP path.
8. Close Registry Editor and restart.

Step 4: Check the Profile Folder Permissions

1. Open C:\Users and right-click your profile folder → Properties → Security.
2. Your account should be listed with Full control, alongside SYSTEM and Administrators.
3. If it is not, click Advanced → Change beside Owner, type your username, click Check Names, then OK. Tick Replace owner on subcontainers and objects and apply.
4. Back on the Security tab, click Edit and grant your account Full control.
5. If the ownership route is unfamiliar, the same procedure is walked through in fix access denied and "you need permission".

Step 5: Repair the Default Profile

Windows copies C:\Users\Default whenever it builds a profile. If that template is damaged, new profiles fail too.

1. In File Explorer, enable View → Show → Hidden items, then open C:\Users\Default.
2. Confirm the folder exists and contains NTUSER.DAT. A missing or zero-byte NTUSER.DAT is the problem.
3. Copy C:\Users\Default from a working PC on the same Windows 11 build, or restore it from a restore point.
4. Then repair the system files: how to run SFC and DISM.

Step 6: Use System Restore From the Recovery Environment

If you cannot sign in to any account.

1. Interrupt the boot three times to reach Automatic Repair, then choose Advanced options.
2. Select Troubleshoot → Advanced options → System Restore.
3. Pick a restore point dated before the sign-in started failing.
4. If no restore points exist, choose Startup Repair instead.
5. Related: fix the automatic repair loop and create a system restore point so this option exists next time.

Step 7: Rule Out Antivirus and Check the Disk

1. If a third-party security suite is installed, uninstall it from the working account and run the vendor's removal tool. Suites quarantining NTUSER.DAT cause exactly this failure.
2. Microsoft Defender takes over automatically: fix Windows Defender not working.
3. Check the file system from Terminal (Admin):

   chkdsk C: /f /r
   

   Press Y to schedule, reboot, and let it finish.
4. Check the drive's health too: check SSD and hard drive health.

Step 8: Build a New Profile and Move Your Files Across

When the old profile cannot be repaired, this recovers everything that matters. A damaged profile is not worth days of fighting.

1. From the working admin account: Settings → Accounts → Other users → Add account → I don't have this person's sign-in information → Add a user without a Microsoft account.
2. Create the account, then set it to Administrator under Change account type.
3. Sign in to the new account once so Windows builds the profile, then sign out and back into the admin account.
4. Copy your data from C:\Users\<oldname> to C:\Users\<newname> — Desktop, Documents, Pictures, Downloads, Videos, and AppData\Roaming for app settings. Do not copy NTUSER.DAT or the whole AppData folder; that carries the damage across.
5. Sign in to the new account and link your Microsoft account if you use one: Settings → Accounts → Your info → Sign in with a Microsoft account instead.
6. Once everything is confirmed working, delete the old account from Settings → Accounts → Other users.

What Not to Do

• Don't delete the profile folder or the registry key before copying your files out. That is what turns a fixable problem into real data loss.
• Don't copy NTUSER.DAT into the new profile. It is the file that is usually corrupt.
• Don't reset or reinstall Windows first. The files are still on the disk and this is repairable.
• Don't edit ProfileList without exporting a backup. A mistyped path there stops every account signing in.

Still Not Working?

If a brand new account also fails to sign in, the problem is system-wide rather than profile-specific — run SFC and DISM, then consider an in-place repair install, which keeps files and apps: reinstall Windows without losing data. Get your data off first: how to recover deleted files in Windows and set up automatic backups.

Related: fix "signed in with a temporary profile", fix Microsoft account sign-in problems, and reset a forgotten Windows password.