The full message reads The User Profile Service failed the sign-in. User profile cannot be loaded. Older versions of Windows say The User Profile Service failed the logon instead. On Windows 11 and Windows 10 it means Windows recognized your account but couldn’t load your profile: the folder under C:\Users plus the registry file inside it, NTUSER.DAT, that holds your settings.
A close cousin is the notice You’ve been signed in with a temporary profile, or We can’t sign in to your account. You get a bare desktop, and anything you save there disappears when you sign out. Both problems usually have the same causes and the same fixes.
In most cases your files are still on the disk, and the order below is built to keep them there: back up, then diagnose, then repair. The fastest clue is whether another account on the PC signs in normally. If it does, it’s a corrupt user profile Windows 11 or 10 can’t load, and only yours is broken. If no account can sign in, suspect disk space, the drive or a recent update, and go carefully: on a failing drive, every repair attempt risks your data.
Try these first
- Do a full restart (not sleep or shut down) and try again; a profile locked by another process often frees up.
- Try a different account on the PC; if it works, only your profile is damaged.
- Hold Shift while selecting Power > Restart, then Troubleshoot > Advanced options > Startup Settings > Restart, and press 5 for Safe Mode with Networking. If the PC is encrypted, have your BitLocker recovery key ready.
- Check that the C: drive has free space; a full drive can stop profiles from loading.
- Before any registry change, copy your C:\Users folder files to a USB drive.
What’s actually broken
Windows keeps a list of every profile on the PC in the registry, under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList. Each account has a key named after its security ID (it starts with S-1-5-21-, or S-1-12-1- for work accounts that sign in with Microsoft Entra ID). Inside, ProfileImagePath points to the profile folder and State holds status flags.
When a profile fails to load, that entry can end up wrong: two keys for the same account, one ending in .bak, or a path pointing to a folder that no longer exists. Windows then gives up or hands you a temporary profile. Use this table to narrow it down:
| What you see | Likely cause | Where to go |
|---|---|---|
| Only your account fails; ProfileList shows a .bak key for your ID | Mismatched profile registry entries | The registry fix below |
| Temporary profile every time, no .bak key | State value not zero, or NTUSER.DAT locked by security or backup software | Set State to 0; check what’s locking the file |
| ProfileImagePath points to a folder that’s gone | Someone deleted the folder under C:\Users by hand | Rebuild the profile the safe way |
| Existing users fine, but anyone signing in for the first time fails | The Default profile Windows copies for new users is damaged | Check the Default profile folder (see other causes below) |
| No account can sign in, or it began after a crash or power loss | Full disk, file system errors or a failing drive | Free space and disk checks first |
| Office PC with a roaming profile, failing only on the network | Profile server or network path | Your admin; see the events below |
| The error is about your PIN, and your password signs in normally | Windows Hello, not your profile | See Something happened and your PIN isn’t available |
First, get in and copy your files
Every fix below is safer once your files are copied somewhere else. You need to reach Windows with an account that has administrator rights.
- Your own account, if Windows signed you in with a temporary profile: you’re in Windows with your normal permissions, just not your settings. Copy your files from
C:\Users\yournamenow; don’t save new work in the temporary profile. If your account is an administrator, open Command Prompt with Run as administrator and create a spare admin account to repair from:net user HelpAdmin * /add(it asks for a password), thennet localgroup Administrators HelpAdmin /add. Restart and sign in as HelpAdmin. On a work PC, ask your admin first. - Another admin account: select it at the bottom left of the sign-in screen, or choose Other user.
- Safe Mode with Networking: hold Shift while selecting Power > Restart, then Troubleshoot > Advanced options > Startup Settings > Restart, and press 5 or F5. Sign in with your password; PINs and fingerprints don’t work in Safe Mode. If the drive uses BitLocker or device encryption, you’ll need the 48-digit recovery key to change startup settings, so find it first; our BitLocker recovery key guide shows where.
If yours is the only admin account and Safe Mode fails too, try System Restore, which doesn’t need your desktop: from the same Advanced options menu, choose System Restore and pick a restore point from before the error started. It rolls the registry, including ProfileList, back without touching your documents, though recently installed apps may need reinstalling. If there are no restore points, stop: creating accounts from recovery tools is easy to get wrong on a PC with important data.
Once in, copy Desktop, Documents, Pictures and Downloads from C:\Users\yourname to a USB drive, plus Outlook signatures from C:\Users\yourname\AppData\Roaming\Microsoft\Signatures and any Outlook .pst files (usually in Documents\Outlook Files; search the profile folder for .pst if they’re not there). AppData is hidden, so type the path into File Explorer’s address bar. If your Desktop and Documents back up to OneDrive, most files are already in the cloud, but anything that hadn’t finished syncing exists only here, so confirm before skipping the copy; our OneDrive sync guide explains how.
Check the event log
Open Event Viewer > Windows Logs > Application, choose Filter Current Log and, under Event sources, tick both User Profiles Service and User Profiles General.
- 1500: the profile couldn’t be loaded.
- 1511: you got a temporary profile. It often comes with 1515 (profile backed up), which usually means a .bak key, covered below.
- 1509 (User Profiles General): profile files couldn’t be copied, from the Default profile at a first sign-in or a roaming profile on an office server.
- 1530: Microsoft says it’s safe to ignore.
For more detail, look under Applications and Services Logs > Microsoft > Windows > User Profile Service > Operational.
The ProfileList bak registry fix: when the key ends in .bak
Warning: A wrong registry edit can break every account on the PC or stop Windows from starting. Copy your files first, export the ProfileList key before changing anything, and change only the one key that belongs to the broken account. On a company PC joined to a domain or to Microsoft Entra ID, let your admin do this.
- Signed in with another admin account, press Win + R, type
regeditand press Enter. - Go to
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList. - With ProfileList selected, choose File > Export and save the file to your USB drive. Double-clicking that file later restores the key.
- Click each key that starts with S-1-5-21- (or S-1-12-1- on a PC signed in with a work account) and read ProfileImagePath in the right pane until you find
C:\Users\yourname. Leave the short system keys (S-1-5-18, -19 and -20) alone.
Now fix what you find:
| What’s there | What to do |
|---|---|
| Two keys with the same ID, one ending in .bak | First confirm the .bak key’s ProfileImagePath points to your real folder. Rename the key without .bak by adding .old to its name. Rename the .bak key to remove .bak. Keep the .old key until you’ve signed in successfully. |
| One key, ending in .bak | Rename it to remove .bak. |
| One key, no .bak, temporary profile anyway | Check that ProfileImagePath matches the folder name in C:\Users exactly. If someone renamed the folder, rename it back or correct the path. |
Then reset the status values
- In the key that’s now your active profile (no suffix), double-click State and set it to 0. If a RefCount value exists, set it to 0 too. Don’t create values that aren’t there.
- Close Registry Editor, restart, and sign in to the repaired account.
If your desktop, files and settings are back, you can delete the leftover .old key. If you still get a temporary profile, import your exported file to put the original keys back, then delete the leftover .old key, which the import doesn’t remove. Then move on to rebuilding the profile.
If the registry looks right: other causes
- Security or backup software holding NTUSER.DAT open. If a profile works after a restart but fails after a backup job or an antivirus scan, check that product’s logs and update it.
- Full drive. Check Settings > System > Storage from a working account and clear temporary files. Windows needs room to load and write the profile.
- File system errors. From an admin Command Prompt run
chkdsk C: /fand answer Y to schedule it at the next restart. If the drive is failing, copy your data before running disk repairs. - Damaged system files. Run
DISM.exe /Online /Cleanup-image /Restorehealth, thensfc /scannow. - A recent update. If it started right after updating, go to Settings > Windows Update > Update history > Uninstall updates (on Windows 10, Settings > Update & Security > Windows Update > View update history > Uninstall updates) and remove the latest one. That also removes its security fixes, so treat it as temporary and let Windows Update reinstall updates once you can sign in. On a company PC, ask whoever manages updates first.
- Only brand-new accounts fail. Windows builds each new profile by copying the hidden
C:\Users\Defaultfolder, so if that folder or its NTUSER.DAT is missing or damaged, every first sign-in fails. Event 1509 usually names the file it couldn’t copy. From an admin Command Prompt, rundir /a C:\Users\Defaultand check that NTUSER.DAT is listed. If not, rename the folder toDefault.oldand copy the Default folder from a healthy PC on the same Windows version (Settings > System > About). Existing profiles aren’t affected. - Roaming profiles or folder redirection. Event 1509 errors that mention a network path point at the profile server, not the PC. That’s a job for whoever runs your office network or IT help desk.
Rather have a technician sort it out?
If another account on the PC still signs in, a technician can connect with your permission, make sure your files are copied and repair the profile without guesswork in the registry. A GoProIT technician can connect remotely, with your permission, and fix it while you watch. $59 per fix, Mon–Fri 8am–8pm ET.
Last resort: rebuild the profile without losing files
If the profile itself is corrupt, give the account a fresh one and move your files across. Microsoft’s supported way to remove a profile is in System Properties: press Win + R, type sysdm.cpl, and on the Advanced tab under User Profiles select Settings, then select the profile and Delete. That deletes the profile folder too, so only use it after you’ve copied everything you need.
A gentler method keeps the old folder intact as your safety net:
- Sign in with a different admin account and restart once so nothing is holding the broken profile.
- Rename
C:\Users\yournametoyourname.old. - In Registry Editor, export ProfileList again. Then delete every key for that account: the one whose ProfileImagePath points to that folder, plus any key with the same ID ending in
.bakor the.oldyou made earlier. A leftover .bak key can bring the temporary profile back. - Sign in to the affected account. Windows builds a brand-new profile.
- Copy Desktop, Documents, Pictures, Downloads, Videos and Music back from
yourname.old, plus your Outlook signatures. Don’t copy NTUSER.DAT or the whole AppData folder, because that can bring the damage with it.
Three things need extra care:
- OneDrive. If OneDrive backed up your Desktop and Documents, sign in and let OneDrive download them; copying the OneDrive folder across creates duplicates. Copy only files that never finished syncing.
- Outlook. Add your email account again; Microsoft 365, Exchange, Outlook.com and IMAP mail downloads again on its own. A POP account keeps all its mail in a .pst file, usually in
Documents\Outlook Filesor, on older setups,AppData\Local\Microsoft\Outlook. Copy it and any .pst archives, then open them in classic Outlook with File > Open & Export > Open Outlook Data File. - Browsers. Unsynced Chrome or Edge bookmarks live in a file named
BookmarksunderAppData\Local\Google\Chrome\User Data\DefaultorAppData\Local\Microsoft\Edge\User Data\Default; copy it to the same place in the new profile with the browser closed. Passwords saved only on this PC usually can’t be moved.
Expect to sign in to Microsoft 365, OneDrive and your browser again, and to re-pin apps. Keep yourname.old until you’ve checked that nothing is missing. On a work PC joined to a domain or Microsoft Entra ID, your admin should do this.
When to stop and get help
Stop and get help instead of trying more fixes when:
- No account on the PC can sign in, or
chkdskreports bad sectors. That points at the drive, and every write makes recovery harder. - The PC won’t reach the sign-in screen at all, or it ends up in repair screens; see the automatic repair loop guide.
- The broken account is the only administrator, and neither Safe Mode nor System Restore helps.
- The problem keeps coming back after every restart, which usually means security software or a policy is involved.
- It’s a work PC with roaming profiles, folder redirection or a domain account.
If another account on the PC can still sign in, this is a typical $59 remote fix: with your permission, a technician connects, makes sure your files are copied before changing anything, then repairs or rebuilds the profile while you watch.
Common questions
Will I lose my files if the User Profile Service fails?
Usually not. The error means Windows couldn’t load your profile, not that it deleted it. Your files stay in your folder under C:\Users until someone removes them. The risk comes from fixes like deleting the profile or resetting Windows before copying files out, which is why every method here starts with a backup.
Will resetting Windows fix the User Profile Service error?
It’s the slowest and most disruptive option, and it isn’t guaranteed to help. Reset this PC with Keep my files reinstalls Windows and removes the apps you installed and the changes you made to settings, so you’d have to set them up again. Repairing the ProfileList entry or giving the account a fresh profile deals with one broken profile in far less time. If you do reset, copy your files to a USB drive first.
Why do I keep getting signed in with a temporary profile?
Windows found your account but couldn’t load your profile, so it created a throwaway one. Common causes are a .bak duplicate in ProfileList, a State value that isn’t zero, a profile path pointing at a renamed or deleted folder, or security software locking NTUSER.DAT. Don’t save work in a temporary profile; it’s deleted when you sign out.
Can I fix this without another administrator account?
Often, yes. If Windows signs you in with a temporary profile and your account is an administrator, copy your files, create a spare admin account from an admin Command Prompt and make the repairs from that account, not from the temporary profile. If you can’t sign in at all, try Safe Mode with your password, then System Restore from the recovery menu. If none of those work, stop rather than experimenting with recovery tools.
Is it safe to delete a profile key from ProfileList?
Deleting the registry key doesn’t delete any files, so it’s reasonably safe once you’ve exported ProfileList as a backup and copied the profile folder. On next sign-in, Windows creates a fresh profile, and app settings and browser passwords saved only on that PC don’t come across. If the old folder still exists with the same name, Windows makes a new folder with a suffix instead, so rename the old folder first.