How to remove an RunDLL32 error

The free file information forum can help you determine if RunDLL32.exe is a virus, trojan, spyware, or adware that you can remove, or a file belonging to a Windows system or an application you can trust.

Click to Run a Free Scan for RunDLL32.exe related errors

RunDLL32.exe file information

The process known as Run a DLL as an App or Windows host process (Rundll32) or Eine DLL-Datei als Anwendung ausführen or Een DLL-bestand als toepassing starten or Exécuter une DLL en tant qu'application or Ejecutar un archivo DLL como una aplicación or Uob or Windows værtsproces (Rundll32)

belongs to software Microsoft Windows Operating System or Betriebssystem Microsoft Windows or Besturingssysteem Microsoft Windows or Sistema operativo Microsoft Windows or Système d'exploitation Microsoft Windows or Microsoft Windows Operativsystem or Lsz or Microsoft DRM

by Microsoft (www.microsoft.com) or Ocf or judokas négligent or Simple Productions or skb or DODQKDZQR or Microsoft Windows Operating System (windows.microsoft.com) or url.

Description: RunDLL32.exe is located in the folder C:\Windows\System32. Known file sizes on Windows 7/XP are 33,280 bytes (60% of all occurrences), 33,792 bytes and 47 more variants.
The file is a Microsoft signed file. Therefore the technical security rating is 6% dangerous, however also read the users reviews.

Recommended: Identify RunDLL32.exe related errors

Viruses with the same file name

Is RunDLL32.exe a virus? No, it is not. The true RunDLL32.exe file is a safe Microsoft Windows system process, called "Run a DLL as an App". However, writers of malware programs, such as viruses, worms, and trojans deliberately give their processes the same file name to escape detection. Viruses with the same file name are for example TROJ_VB.CHK or PE_VIRUT.AV (detected by TrendMicro), and generic!bg.gyj (detected by McAfee).
To ensure that no rogue RunDLL32.exe is running on your PC, click here to run a Free Malware Scan.

How to recognize suspicious variants? If RunDLL32.exe is located in a subfolder of C:\Windows, the security rating is 27% dangerous. The file size is 44,544 bytes (65% of all occurrences), 34,816 bytes and 25 more variants. The program is not visible. RunDLL32.exe is a trustworthy file from Microsoft.

If RunDLL32.exe is located in a subfolder of "C:\Documents and Settings", the security rating is 56% dangerous. The file size is 24,576 bytes (25% of all occurrences), 120,992 bytes and 11 more variants. The file is not a Windows core file. There is no description of the program. The program is not visible. Program is loaded during the Windows boot process (see Registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run, HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run, HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Runonce, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce, HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Run, HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell, C:\Windows\win.ini, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Userinit, HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders). RunDLL32.exe is able to record inputs.

If RunDLL32.exe is located in the folder C:\Windows, the security rating is 69% dangerous. The file size is 1,264,832 bytes (15% of all occurrences), 135,168 bytes and 13 more variants.

If RunDLL32.exe is located in a subfolder of "C:\Program Files", the security rating is 48% dangerous. The file size is 33,280 bytes (15% of all occurrences), 33,792 bytes and 8 more variants.

If RunDLL32.exe is located in the folder "C:\Program Files\Common Files", the security rating is 66% dangerous. The file size is 178,180 bytes (63% of all occurrences), 183,296 bytes or 187,904 bytes.

If RunDLL32.exe is located in a subfolder of C:\Windows\System32, the security rating is 70% dangerous. The file size is 26,112 bytes (20% of all occurrences), 1,930,240 bytes, 376,851 bytes, 71,168 bytes or 256,512 bytes.

If RunDLL32.exe is located in a subfolder of C:\, the security rating is 69% dangerous. The file size is 61,440 bytes (75% of all occurrences) or 589,874 bytes.

If RunDLL32.exe is located in a subfolder of Windows Temp folder, the security rating is 56% dangerous. The file size is 310,359 bytes.

If RunDLL32.exe is located in a subfolder of the "My Files" folder, the security rating is 56% dangerous. The file size is 7,168 bytes.

External information from Paul Collins:
There are different files with the same name:

"BatInfEx" can run at start up. Displays battery status information on an IBM Thinkpad
"LoadPowerProfile" definitely not required. Added by the MIROOT WORM! Note - do not confuse with the valid LoadPowerProfile entry which has "powrprof.dll" appended to the command/data line
"Rundll32" definitely not required. Added by the DVLDR TROJAN! Note - this is not the valid "Rundll32.exe" as it's in the Windows\Fonts directory
"rundll32" definitely not required. Added by the SANKER WORM! Note that the valid "rundll32.exe" resides in C:\Windows\System32 wheras this version resides in C:\Windows
"TaskMan" definitely not required. Added by the DVLDR TROJAN! Note - this is not the valid "rundll32.exe" as it's in the Windows\Fonts directory
"UPDATEHOOK": ??
"Win32 Rundll Loader" definitely not required. Added by the SDBOT.A TROJAN! Note: Rundll32.exe is a valid Windows application called "Run a DLL as an App" and stored in the C:\Windows directory. The version created by this virus is saved in the C:\Windows\System directory
"Windows DLL Loader" definitely not required.

Important: Some malware camouflages itself as RunDLL32.exe, particularly when located in the c:\windows or c:\windows\system32 folder. Therefore, you should check the RunDLL32.exe process on your PC to see if it is a threat. We recommend Security Task Manager for verifying your computer's security. This was one of the Top Download Picks of The Washington Post and PC World.

Score

User Comments

run dll32.exe can be both harmful and neutral, what it is, is a execution program run by windows so that it can startup all the windows nonsense like explorer.exe, but some clever person from poland in 1980s found a way they could use this to run a selected program that they have planted on your computer, ie a virus downloaded from the internet because normally they would have to make there own executional file to start the virus process, but using the rundll32.exe was much better because it could use it as a way to mask itself and tricked antivirus software into thinking that it was windows opening the dll until Dr. Solomon created his Anti-Virus Tool-kit to remove them. if it appears in upper case letters then it will probably be some home made virus and i would consider removing it, ps, ANDREW - the *32 is normal it just means that you have a 32 bit computer, (how many bits of data your computer uses) but you don't need to know the technical stuff.
Richard

Don't touch or edit the file lets pretend it it is the you kill it you kill kernel32.dll = computer dies :( see your self
Vincent Bartolo

This is a valid Windows program used to run DLLs (hence the name). YES there are also viruses out there that use the same name, and YES viruses can exploit and screw with your rundll32.exe file, just as they can screw with any of your files, and YES sometimes you will have system or registry errors that cause it to not run properly... but the file itself is safe, valid, and necessary for certain functions. If you're having rundll32.exe problems, rundll is not the cause, unless you have a second illegitimate rundll32 file hiding on your system somewhere.
D

The file itself is not dangerous and it is an essential file in windows. But malwares might use it the run dangerous code!!! Anyway, DON'T DELETE IT.
Anonymous

this does a lot of functions in dll files like the run dialog. but a lot viruses use this too.
Oskar

for me in task manager it is called rundll32.exe *32 i'm not sure if its safe...the *32 throws me off
Andrew

When is shut down my computer its giving error ending program.. please wait above that message box heading as end program - rundll32.exe
Ramesh Narne

When I try to turn off my computer rundll32.exe pops up, and the only way to turn off my computer is to "end process".
Mark

More comments can be found here:
(further information)

Summary: Average user rating of RunDLL32.exe: based on 460 votes with 9 reviews.

162 users think RunDLL32.exe is essential for Windows or an installed application. 21 users think it's probably harmless. 113 users think it's neither essential nor dangerous. 67 users suspect danger. 97 users think RunDLL32.exe is dangerous and recommend removing it. 76 users doesn't grade RunDLL32.exe ("not sure about it").

RunDLL32 scanner

Security Task Manager shows all running Windows tasks including embedded hidden functions (e.g. keyboard or browser monitoring, autostart entry). A unique security risk rating indicates the likelihood of the process being potential spyware, malware, keylogger or a Trojan.

MalwareBytes detects and removes sleeping spyware, adware, trojans, keyloggers, malware and tracking threats from your hard disk. Ideal supplement to Security Task Manager.

SpeedUpMyPC scans, cleans, repairs and optimizes your computer.

Other processes