logonui.exe is a program which is most likely NOT a virus. So, if logonui.exe is on your system, it is most likely ok, and will NOT be a cause for concern. Even if your PC is virus-free, it is still recommended to run a well-known antivirus with a good detection rate, in order to yourself your system against potential security problems.
The default filename and folder where the program is stored is
C:\Windows\System32\LogonUI.exe.
The MD5 checksum for this file is 715f03b4c7223349768013ea95d9e5b7.
This application does NOT operate as a Windows service. This is usually a good sign.
logonui.exe seems to use the functions of Windows SFC (System File Checker) or Windows File Protection.
64-bit code has been detected. This application can use the full power of a modern PC cpu.
logonui.exe is digitally signed. Today the large majority of clean software applications are digitally signed.
The digital signature extracted from logonui.exe is valid. This is most likely a clean, ok program.
Digital certificate name: Microsoft Windows
Certificate's issuer name: Microsoft Windows Verification PCA
This executable does NOT have a removal routine stored in registry.