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🔐 Windows Login Fix

User Profile Service Failed the Sign In Windows Login Issue Fix

You type the correct password, Windows thinks for a moment — and instead of your desktop you get one cold line: The User Profile Service failed the sign-in. Your password is fine. Your files are fine. The registry entry that loads your profile is damaged, and it can usually be repaired in minutes without reinstalling anything.

✍️ Technical Anshu🪟 Windows 10 / 11⏱️ 10 minute fix
🎥 Watch the video — the second admin account and the registry repair, done live step by step

Every login failure looks the same from the chair — you are locked out of your own PC. But underneath, they split into families: profile damage, password trouble, slow loading, and a few more. The exact wording on your screen tells you which family you are in, and each family has a different fix. This guide is the triage: it fixes the profile family — the one in the video above — properly, and shows you exactly where the other families split off, so you never spend an evening applying the right medicine to the wrong disease.

The sign-in screen — the exact message this guide is about
The User Profile Service failed the sign-in.
User profile cannot be loaded.
You click OK — and Windows takes you straight back to the sign-in screen.
📷 The profile family error, word for word. If your screen says something else, your fix is different — Fix 1 below sorts that out.
1

First, Confirm Your Failure Is Really the Profile Family

Sign-in failures split into families, and each family has a different medicine. The wording on screen is the diagnosis, so read it before touching anything:

  1. "The User Profile Service failed the sign-in" — the profile family. That is this guide, and the video above.
  2. "We can't sign in to your account" — you have been given a temporary profile. A close cousin, but a different fix.
  3. "The password is incorrect" — an account and password problem, not a profile problem. Trying profile repairs there wastes your evening.
  4. No message at all — black screen, or the Welcome dots spin forever. Those are load problems, covered by their own guides.

One more confirmation: if another account on the same PC signs in normally, your Windows, your disk and your password system are all healthy — only this one profile is damaged. That is the strongest sign you are in the right guide.

2

Get In Through a Second Administrator Account

The repair happens from inside Windows, so first you need a door. The broken account cannot open its own desktop, but any other administrator account on the PC can:

  1. On the sign-in screen, pick the other user and sign in normally.
  2. Check it is an administrator: Settings → Accounts → Your info should say Administrator under the name.
  3. Stay signed in as this account for all the repair steps below. You are fixing the broken profile from outside it — the profile must stay unloaded while you work.

If the PC has only one account and it is the broken one, do not panic and do not reinstall. Safe Mode is the second door for exactly this situation — there is a separate guide for it in this series. On an office PC joined to a company domain, stop here and call IT instead: profile repairs touch domain settings that IT owns.

3

Repair the Profile Entry in the Registry ⭐

Windows keeps a list of every profile in the registry, with the folder each account should load. In this failure, that one entry is damaged — usually renamed with a .bak ending, or its counters are wrong — so Windows refuses to load the profile even though the folder is sitting there, full of your files.

  1. Press Windows + R, type regedit and open the Registry Editor as the administrator account.
  2. Back up first: click File → Export and save a copy of the registry. This is your undo button.
  3. Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
  4. The sub-keys named S-1-5-21-... are the accounts. Click each one and read ProfileImagePath on the right — find the one that points to the broken account's folder, for example C:\Users\Ansar.
  5. If that key ends in .bak, a plain twin key with the same name usually exists too. Rename the plain one by adding .ba to its name, then rename the .bak one by removing .bak.
  6. Inside the repaired key, double-click RefCount and set it to 0, then double-click State and set it to 0.
  7. Close the editor and restart the PC. Sign in with the repaired account — the desktop, files and settings should all be back.

The video above takes the faster road to this same repair: it provides a ready-made registry fix file in the description. Sign in as the other administrator, download it, double-click it, and restart. One honest safety rule whichever road you take: open any registry file in Notepad before merging it and confirm the entries under it point at the ProfileList key named above. A registry file you have not read is a letter you sign without opening.

4

After It Loads, Check Why It Broke

A profile rarely corrupts itself. The usual causes are a forced shutdown, a disk developing errors, or damaged system files — and if the cause is still there, the error will be back within weeks.

  1. Open Terminal or Command Prompt as administrator and run sfc /scannow. Let it finish; it repairs damaged Windows system files.
  2. If the error returns after this, test the drive's health next — a profile that keeps breaking is often the first visible symptom of a tiring disk.
  3. From now on, shut down normally. Holding the power button is sometimes necessary, but as a habit it is hard on profiles.
5

If the Entry Is Beyond Repair, Build a Fresh Profile

Sometimes the registry entry can be fixed and the profile still refuses to load — the folder itself is damaged. The honest ending then is a new profile, which is a move, not a loss:

  1. From the administrator account, create a new local account and make it an administrator.
  2. Sign in to it once, so Windows builds its folders, then sign back into the working admin account.
  3. Copy Documents, Desktop, Downloads, Pictures and Videos from C:\Users\OldName into the matching folders of the new profile.
  4. Do not copy the whole profile folder or the NTUSER.DAT file — that carries the corruption into the new home.
  5. Use the new account for a week. Only when everything you need is confirmed working, delete the old account.
🔴 Office PC? Read this first. If your sign-in screen shows a company name, or the PC was issued by your employer, this is a domain account — profile surgery is IT's job, and a wrong step can break the PC's trust with the company network. Call your IT team and tell them the exact message from Fix 1; you will get fixed faster than any colleague who just says "login is not working".

🎥 Watch the Complete Process in the Video

Watch the complete repair in the video — a second administrator account, the ready-made registry fix, and the account opening again, all shown live.

▶️ Watch Full Video
❓ Frequently Asked Questions

Will this fix delete my files?

No. Your files live in your profile folder, usually C:\Users\YourName, and this error does not delete them — Windows simply refuses to load the folder because its registry entry is damaged. The repair in this guide only fixes that entry. Copying your important files to a pen drive from the working admin account, before you start, is still a wise two minutes.

I have only one account on this PC, and it is the broken one. How do I get in?

Try Safe Mode first — it loads a minimal Windows and is the standard second door for repairs when no spare account exists; this series has a full guide for reaching it when sign-in is broken. If Safe Mode also refuses, the recovery environment can create a new administrator account. And if the PC belongs to your employer, skip all of this and call IT — it is a domain account and it is their repair to make.

The error came back a few days after I fixed it. Why?

A repaired entry breaking again means the cause is still active. The common ones are a hard disk developing errors, repeated forced shutdowns, or damaged system files that the sfc /scannow check in Fix 4 did not fully cure. Treat a returning profile error as a warning light: back up your files now, then check the drive's health properly before it fails in a bigger way.

This guide is based on the Technical Anshu Windows login fix video • Stuck on any step? Ask in the video comments — you will get a reply there 🙏