Before moving on to the actual process of resolving this, here is a backgrounder on the RUNDLL error: What is it, and how does it come about?
What is a RUNDLL Error?
First up, a rundll.exe file is a system process directly involved with the running of your Windows OS. DLL files are part and parcel of a large data and code network that various computer programs share. These files help to render your operating system’s efficiency in terms of processing speed and memory. How? These files do this by reapplying the same file or code to activate various functions run by different programs. When a particular application is unable to access this specific piece of data, an error happens.
This error manifests itself in a “<program/application> could not be found” status message. Statistics estimate the problem to be quite widespread, as more than 90% of computers have or will potentially contract such errors. Even if a certain computer is virtually brand-new, it may not operate optimally even after a short period due to this registry concern.
Why does a RUNDLL Error occur?
A RUNDLL error may be caused when a DLL file goes missing or gets corrupted; with any program which needs that file to function. The direct reasons why these RUNDLL error messages pop up (or why the DLL file is missing) may be due to any of the following:
• A system may have linked straight to a virus or piece of spyware. Some kinds of malware or spyware often attempt to control files that the RUNDLL file shares.
• A system registry may have linked to invalid entries. This may occur due to improperly uninstalled or previously removed software.
If these invalid entries are eliminated, applications which share the DLL file gain better efficiency; thus ideally increasing the performance of a computer system.
How to Fix a RUNDLL Error
Identify the RUNDLL Process
Picking out one specific process out of a whole slew of others seems daunting. Considering that there are legions of process libraries you can find online mitigates the difficulty of this step. An online process library can help you discern whether a running process is valid or not.
Take note of the process name involved when an error dialog window appears on your screen. If a dialog pops up and shows a DLL error, log on to the Internet and go to a site like
ProcessLibrary.com - The online resource for process information!. This site will have a search box wherein you can enter (or simply copy and paste) the specific file name. The resulting message that you get from the website after entering the name will indicate if it is invalid, and thus part of any malware or spyware.
Halt the RUNDLL Process
The RUNDLL code can found in the “exe” files list of services most of the time. Open the services configuration with the following steps:
• Go to the Start Menu and click on ‘Run’.
• Enter <services.msc> in the command screen. This will activate the window for Services Management.
• Drag the cursor to any of the services. Right-clicking on one will give you details about the service.
• Stop the dubious DLL service.
Locate and Erase the RUNDLL Process
Access the file system for your computer’s Windows Registry. The riskiness of this procedure cannot be emphasized enough. This step mostly resolves the DLL problem, as well as erases other errors, thus speeding up your system. Proceed with caution.
• Go to the Start Menu and click on ‘Run’.
• Enter <regedit> in the search box.
• Locate the following registry key: HKEY_LOCAL_MACHINE> SOFTWARE\ Microsoft\ Windows\ CurrentVersion\ RUN
• Click on the associated DLL file (refer to the invalid process name from the first step: Identify the DLL Process)
• Delete the invalid process’ value and restart your computer.
Notes and Recommendations
The rundll.exe file and process is extremely vital to the operation of your computer. Conversely, its back-door susceptibility to various malware and similar code is quite immense. Through this, an attacker may easily access your passwords, banking information, and other important data from your computer.
Typically, trojans also use this pathway to hijack other processes, and invite further infection by other Trojans or more spyware. Keeping your computer’s security software current while observing your system’s DLL processes is the best type of prevention.
If the abovementioned steps, however, fail to resolve the issue, resort to one of any reputable registry cleaners available on the Internet.
A Quick Fix for the RUNDLL Error 
