What is rundll32.exe?

Windows Process Description:
The rundll32.exe process and the rundll.exe process is a utilty program for Microsoft Windows 95, Windows 98, and Windows Millennium Edition.

The rundll32.exe utility program allows the user to invoke a function called from either a 16-bit or 32-bit DLL. However, it is not possible to call any exported function from any DLL through the rundll32.exe application. The rundll32.exe process and rundll.exe process only allows users to call functions from explicitly written DLL.

The rundll32.exe process also works by executing DLLs and placing their libraries into the system’s memory. This allows these DLLs to be easily called by other applications that requires the DLLs function.

The file rundll32.exe is an essential system file for Windows. The process rundll32.exe uses 33280 bytes worth of RAM and is commonly located in the folder C:\ Windows\ System32. Other known file sizes ranges from 31,744 bytes to 610,304 bytes. The rundll32.exe file is a trustworthy Microsoft file and is advisable that this process should not be altered or deleted from the system.

This executable file rundll32.exe is sometimes used as a disguise by some malwares which usually resides on the Windows folder. These illegitimate rundll32.exe files are known to adversely affect your system’s performance and is highly recommended that you constantly check abnormal memory usage of certain files that uses the same file name as the rundll32.exe file.

The process rundll32.exe loads and runs 32-bit bit DLLs as compared to rundll.exe file which only runs 16-bit DLLs. Passing the wrong type of DLL on either rundll32.exe process or rundll.exe process may cause the program to fail without indicating any error messages.

The rundll32.exe process works through the following steps: (1) The process parses the command line. (2) It loads the specified DLL via Load Library. (3) It calls the function and passes the command line tail. (4) When the function returns, rundll32.exe unloads the specified DLL and terminates.

Microsoft Corporation

Author URL:

Part Of:
Microsoft Windows Operating System

Memory Usage:
Low. The rundll32.exe uses 33280 bytes worth of RAM resources.

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