User Profile Service Failed Login Load Fix

Quick answer for advanced users

Boot into Safe Mode, open Regedit, navigate to HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList. Find the SID folder for your user (look for the one without .bak and check State is 0 and RefCount is 0). Delete any SID with a .bak suffix, then rename the .bak back to the original SID. Reboot.

What's actually happening here

Windows stores every user profile’s settings under a unique Security Identifier (SID) in the Registry. When you log in, the User Profile Service reads this key. If the key gets corrupted—usually after a hard crash, disk error, or interrupted Windows update—Windows can't read the profile path, so it throws that “failed the logon” error and logs you in with a temp profile instead. The machine thinks the profile is “in use” (RefCount > 0) or “pending deletion” (State > 0), so it refuses to load it.

This isn't a driver issue or a virus. It's a registry lock. Most “fixes” you see online tell you to create a new user account and migrate data. That works, but it's slow and you lose app settings. The real fix is to clear those two registry flags and remove the orphaned backup keys Windows created when it panicked.

Fix steps

1. Boot into Safe Mode. Restart your PC, press F8 (or Shift + Restart from the login screen) and choose Safe Mode with Networking. You need admin rights to edit the registry.
2. Open Regedit. Press Win + R, type regedit, hit Enter.
3. Navigate to the ProfileList key. Go to:
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
4. Find your SID. Under ProfileList, you'll see a list of SID folders (long strings like S-1-5-21-...). Click each one and look at the ProfileImagePath value on the right. Find the one that points to C:\Users\YourUsername. For some SIDs, you'll see a duplicate with .bak at the end—that's the backup Windows created when the profile got corrupted.
5. Check the flags. For the SID without .bak, double-click State and make sure it's 0. Then check RefCount — it must be 0. If either is not zero, that's why the profile fails to load.
6. If State or RefCount isn't zero: Set both to 0. Right-click the value, Modify, type 0, click OK.
7. Delete the .bak key. Right-click the SID folder that has .bak in its name (e.g., S-1-5-21-...-1001.bak) and choose Delete. Confirm.
8. If you have more than one .bak: Windows may have created multiple backups. Keep the one that corresponds to your current profile (check the ProfileImagePath on each .bak). Delete the others.
9. Reboot normally. Log in with your username. The profile should load without the error.

Alternative fixes if the registry route doesn't work

Sometimes the registry is fine but the profile folder itself got corrupted. Here's what to try:

• Run SFC / DISM. Open Command Prompt as admin, run sfc /scannow, then DISM /Online /Cleanup-Image /RestoreHealth. This fixes system file corruption that can affect profile loading.
• Create a new user and migrate manually. Boot into Safe Mode with another admin account (or use the built-in Administrator account). Create a new user via Settings > Accounts > Family & other users. Log into the new account, then copy files from C:\Users\OldUsername to the new profile. You'll lose app-specific settings like browser extensions or Outlook profiles, but your documents, pictures, and desktop files survive.
• System Restore. If the error started after a specific update or driver install, roll back with System Restore to a point before the problem. This doesn't touch your files, just system state.
• Check disk for errors. Run chkdsk C: /f from an admin command prompt. Bad sectors on the drive can corrupt profile files. This takes a while but can prevent recurrence.

Prevention tip

This error usually hits after a forced shutdown—like a power loss or a BSOD. The registry write that marks your profile as “active” gets interrupted, leaving that RefCount stuck at 1. To avoid this:

• Always shut down properly. Never hold the power button unless the machine is frozen for more than 30 seconds.
• If you're on a laptop, don't let the battery die while logged in. Plug it in.
• Keep a recent backup of C:\Users\YourUsername and the registry key ProfileList. Export that key once a month and save it somewhere safe. If the error hits again, you can import it in Safe Mode and skip the whole SID hunt.

One last thing: if you see the error but your desktop still loads (you can click Start and open apps), that's a temp profile. Don't save anything important while logged into it—changes get written to a temp folder and vanish on next reboot. Fix the registry first, then log out and back in.