How to fix Logonui.exe system error on boot

How to fix Logonui.exe system error on boot: When you power ON your PC you suddenly get an error LogonUI.exe – Application error at the login screen and you are stuck at the screen, leaving you to forcefully shutdown the PC in order to get rid of the error. The main cause of this error is obviously LogonUI.exe file which somehow got corrupted or is missing which is why you are facing this error.

LogonUI is a Windows program responsible for the interface you get on the log on screen but if there is a problem with the LogonUI.exe file then you will get an error and you won’t be able to boot into Windows. So without wasting any time let’s see how to actually fix Logonui.exe system error on boot with the below-listed troubleshooting guide.

Contents

• How to open Command Prompt using Installation Media
• How to fix Logonui.exe system error on boot
• Method 1: Run Automatic/Startup Repair
• Method 2: Run DISM (Deployment Image Servicing and Management)
• Method 3: Use System Restore using Troubleshoot screen
• Method 4: Run System File Checker (SFC) and Check Disk (CHKDSK)
• Method 5: Repair your Boot sector or Rebuild BCD
• Method 6: Rename Program Files Folder

How to open Command Prompt using Installation Media

a)Put in the Windows installation media or Recovery Drive/System Repair Disc and select your language preferences, and click Next.

b)Click Repair your computer at the bottom.

c)Now choose Troubleshoot and then Advanced Options.

d)Select Command Prompt (With networking) from the list of options.

Now that you know how to open the command prompt using Windows Installation media we can continue with our troubleshooting guide.

How to fix Logonui.exe system error on boot

Method 1: Run Automatic/Startup Repair

1.Insert the Windows 10 bootable installation DVD and restart your PC.

2.When prompted to Press any key to boot from CD or DVD, press any key to continue.

3.Select your language preferences, and click Next. Click Repair your computer in the bottom-left.

4.On choose an option screen, click Troubleshoot.

5.On Troubleshoot screen, click Advanced option.

6.On the Advanced options screen, click Automatic Repair or Startup Repair.

7.Wait til the Windows Automatic/Startup Repairs complete.

8.Restart and you have successfully Fix Logonui.exe system error on boot, if not, continue.

Also, read How to fix Automatic Repair couldn’t repair your PC.

Method 2: Run DISM (Deployment Image Servicing and Management)

1.Open Command Prompt using the above method.

2.Enter the following command in cmd and hit enter:

DISM.exe /Online /Cleanup-Image /RestoreHealth

2.Press enter to run the above command and wait for the process to complete, usually, it takes 15-20 minutes.

NOTE: If the above command doesn't work then try on the below: Dism /Image:C:\offline /Cleanup-Image /RestoreHealth /Source:c:\test\mount\windows Dism /Online /Cleanup-Image /RestoreHealth /Source:c:\test\mount\windows /LimitAccess

Note: Replace the C:\RepairSource\Windows with the location of your repair source (Windows Installation or Recovery Disc).

3.After the DISM process if complete, type the following in the cmd and hit Enter: sfc /scannow

4.Let System File Checker run and once it’s complete, restart your PC.

Method 3: Use System Restore using Troubleshoot screen

1.Put in the Windows installation media or Recovery Drive/System Repair Disc and select your language preferences, and click Next

2.Click Repair your computer at the bottom.

3.Now choose Troubleshoot and then Advanced Options.

4..Finally, click on “System Restore” and follow onscreen instructions to complete the restore.

5.Restart your PC and this step may have Fix Logonui.exe system error on boot but if it didn’t then continue.

Method 4: Run System File Checker (SFC) and Check Disk (CHKDSK)

1.Again go to command prompt using the method 1, just click on command prompt in the Advanced options screen.

2.Type the following command in cmd and hit enter after each one:

sfc /scannow /offbootdir=c:\ /offwindir=c:\windows chkdsk C: /f /r /x

Note: Make sure you use the drive letter where Windows is currently installed

Note: In the above command C: is the drive on which we want to run check disk, /f stands for a flag which chkdsk the permission to fix any errors associated with the drive, /r let chkdsk search for bad sectors and perform recovery and /x instructs the check disk to dismount the drive before beginning the process.

3.It will ask to schedule the scan in the next system reboot, type Y and hit enter.

4.Exit the command prompt and restart your PC.

Method 5: Repair your Boot sector or Rebuild BCD

1.Using above method open command prompt using Windows installation disk.

2.Now type the following commands one by one and hit enter after each one:

a) bootrec.exe /FixMbr b) bootrec.exe /FixBoot c) bootrec.exe /RebuildBcd

3.If the above command fails then enter the following commands in cmd:

bcdedit /export C:\BCD_Backup c: cd boot attrib bcd -s -h -r ren c:\boot\bcd bcd.old bootrec /RebuildBcd

4.Finally, exit the cmd and restart your Windows.

5.This method seems to Fix Logonui.exe system error on boot but if it doesn’t work for you then continue.

Method 6: Rename Program Files Folder

1.Open the command prompt using above method and type the following command:

ren “C:\Program Files” “Program Files-old”
ren “C:\Program Files (x86)” “Program Files (x86)-old”

2.Reboot your PC normally and then remove the “-old” from the above folders by again renaming them.

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That’s it you have successfully learned How to fix Logonui.exe system error on boot but if you still have any questions regarding this guide then feel free to ask them in the comment’s section.