What is user32.dll?

User32.dll is Windows USER API Client DLL. Sometimes it’s called Multi-User Windows USER API Client DLL.

This file is part of Microsoft® Windows® Operating System. User32.dll is developed by Microsoft Corporation. It’s a system and hidden file. User32.dll is usually located in the %SYSTEM% sub-folder and its usual size is 578,560 bytes.

The user32.dll process implements the Windows USER component. This component creates and manages the standard elements of the Windows user interface, such as the desktop, menus, and windows. User32.dll makes it possible for programs to implement a graphical user interface that matches the Windows look.

Applications call functions from Windows USER to perform tasks like creating and managing windows, displaying text in a program window, and showing message boxes.

Windows uses the user32.dll file to store instructions for graphical elements, such as dialog boxes and windows. This makes the user32.dll file necessary to the operation of Windows. If this file gets damaged or deleted, the system will no longer work properly.

How to Fix user32.dll Errors

In most cases, user32.dll errors can be corrected by simply reinstalling the program or the driver that is causing the error. If that doesn’t help, System Restore can be used to revert any recent changes that might have caused the problem.

User32.dll error messages usually describe the source of the error and include the information about the involvement of the user32.dll file. This is true for the “Illegal system DLL relocation“ error and other related user32.dll errors. The most common cause of this problem is outdated program components, which means that it can be fixed by running Windows Update. You can either launch Windows Update from the Control Panel or do the following:

1. Click on Start and click on Run
2. Type wupdmgr in the Run box and hit Enter

Sometimes the user32.dll error appears during or after installing a program, a driver or a hardware component. To fix that, you should uninstall the newly installed item, reboot your computer and install it again.

If the previous steps don’t help, use the System File Checker tool to repair the user32.dll file. If System File Checker discovers that a protected file has been damaged, it retrieves the correct version of the file from the DLL cache folder (%Systemroot%\System32\Dllcache) or from the Windows installation source files, and replaces the damaged or overwritten file.

To launch the System File Checker, do the following:

1. Click on Start and click on Run.
2. Type sfc.exe in the Run box and hit Enter. Let the tool scan your system files.