FIX: LogonUI.exe Error on BOOT/Start-up
Nothing’s more terrifying than getting an error before your computer even turns on completely. In this specific case, users have reported getting a LogonUI.exe – Application Error at the log in screen. The severity of the error is such that the user is unable to click on anything on the log on screen and the only option they have is to forcefully shut down the computer rendering computer useless.
LogonUI is a Windows program which is responsible for the interface you see on the log on screen. This error that you are getting indicates that either the Logonui.exe file itself has gotten corrupted, or another program is interfering and causing the LogonUI to produce such results.
Our guide below will cover both the sides of the issue plus other probable causes of this error too.
It has been reported that KB3097877 is causing this issue as well. For professionals, if they can remotely connect and perform command line based instructions, remove the update KB3097877 remotely using the following command:
wusa /uninstall /kb:3097877 /quiet
Solution 1: Run DISM Repair
This error can caused if the LogonUI program on your computer is faulty. To repair it, we will have to log in to safe mode with command prompt.
To do so, power on your system and then forcefully shut down your computer when it reaches the Windows logo. Repeat these steps from 4 to 5 times and at some point you will get Preparing for Automatic Repair under the Windows logo. Let it run this time.
In the Automatic Repair screen, click on Advanced Options > Troubleshoot > Advanced Options > Command Prompt.
Command Prompt with a black window will open. In it type Dism /Online /Cleanup-Image /RestoreHealth and Press Enter.
Windows will repair any system file it finds corrupt.
Once the process completes, check if the issue resolved. If not, you might have to repair the System files from an installation media.
To do so, create an installation media by following Method 5 in our guide here and once you reach Advanced Options, select Safe Mode with Command Prompt.
Your computer will now boot into safe mode with a command prompt window.
First, you will have to confirm the drive letter of the installation media you inserted. To find that, in the black window type D: and Press Enter. If in the list that appears, you see folders such as boot, efi, sources, then this the installation media.
If not, press E: and Press Enter and check the names of the folders. Keep on checking the drive letters, and note down the drive letter on which those folders appear. In this guide, we will assume it is drive letter E:.
Now type Dism /Image:C:\ /Cleanup-Image /RestoreHealth /Source:wim:D:\Sources\Install.wim:1 /limitaccess and Press Enter.
Once the process is complete, restart your computer. The problem should be gone now. If not, move on to the next solution.
Solution 2: Uninstall FastAccess or other Such Security programs
If you have installed Facial Recognition software programs such as FastAccess, then their incompatibility with Windows 10 can cause this issue to happen.
To do so, power on your system and then forcefully shut down your computer when it reaches the Windows logo. Repeat these steps from 4 to 5 times and at some point you will get Preparing for Automatic Repair under the Windows logo. Let it run this time.
In the Automatic Repair screen, click on Advanced Options > Troubleshoot > Advanced Options > Startup Settings
Click Restart.
After restart when you reach the Startup Settings screen, Press F4 for safe mode.
Once you log in, Press and Hold the Windows key and Press R. Type appwiz.cpl and Press Enter. Locate FastAccess or any such security program. Right click on it and Click Uninstall.
If the LogonUI error appears in the Safe Mode too, disabling you from logging in, then reach the command prompt using the instructions in Solution 1.
In the command prompt windows, type ren “C:\Program Files” “Program Files-old” and Press Enter.
Now type ren “C:\Program Files (x86)” “Program Files (x86)-old” and Press Enter. No need to worry even if it gives an error Proceed anyway.
Now restart your computer and log in normally.
Open your C drive and remove -old from the names of Program Files and Program Files (x86) folder.
Now, Press and Hold the Windows key and Press R. Type appwiz.cpl and Press Enter. Locate FastAccess or any such security program that look suspicious. Right click on it and Click Uninstall.
Now restart your system and check.
Solution 3: Disable Graphic Card Adapter
A temporary issue with your graphic adapter can also cause LogonUI program to react like this. To remedy this, we will disable the graphic adapter in safe mode, then update and enable it normal mode.
Boot into safe mode by following our guide here.
Once you log into safe mode, Press and Hold Windows key and Press R. Type devmgmt.msc and Press Enter.
In the Device manger window, expand Display Adapters and Right click on the device under it. Click Disable.
Restart your system and you should be able to log in normally.
Now similarly, enable the device through Device manager.
Right click on the device and click Update Driver Software.
In the Update Windows, click on Search Automatically for updated driver software.
It will automatically search and install updated drivers, if available. Also check on your graphic card’s manufacturer’s website for the latest drivers for Windows 10.
