What is Windows DLL?
Dynamic Link Library (DLL) files are libraries of executable functions and codes that are used by a Windows operating system and the applications installed on it to perform various functions. DLL files are linked to programs using either static or dynamic links. A static link is formed when a program is linked to a DLL throughout its operation. A dynamic link is formed when a program uses a DLL only when required. Most of the DLL files have .dll, or .exe extensions.
The best thing about DLL files is that they can be used across multiple applications at the same time. Windows operating systems come with a few pre-installed DLLs that can be used by any application installed on it. Most of the other DLLs are usually developed to be used by a specific application and are loaded only when you launch that application.
What do you mean by DLL Hell?
DLL Hell is the term used to refer to Windows DLL errors that generate due to various problems. Some of the common causes of Windows DLL errors are discussed here.
The most common cause of Windows DLL errors is when a newly installed application replaces a DLL with an older version. Now, because a DLL is used across various applications, overwriting of a new version of DLL file may start causing errors in other applications using this DLL. Therefore, developers should make sure that their applications match the versions of DLLs already existing on the system before overwriting them. In addition to this, even you as a user must ensure that if prompted, you choose to retain the newer versions of DLL files on your system.
For instance, when trying to empty the Recycle Bin, you may receive the following error:
This program has performed an illegal operation and will be shut down. If the problem persists, contact the program vendor.
This error is usually displayed when the C:\Windows\System\Msvcrt40.dll file is either damaged or is replaced by another program.
Windows DLL errors also occur if a shared DLL is deleted when you uninstall an application. In such a situation a missing DLL error is generated whenever an application is not able to locate to DLL.
Faulty hardware—especially faulty hard disk drives or malfunctioning memory, corrupt registry, and problems in various applications can also damage DLL files leading to Windows DLL errors.
For instance, you may receive an error message:
Windows could not start because the following file is missing or corrupt:
C:\system32\hal.dll. Please re-install a copy of the above file.
This indicates that the Hall.dll is either damaged or missing. The error is more common in multiboot operating systems, on which a damaged boot.ini file can display the message.
One of the most common causes of Windows DLL errors is infestation by malicious software—especially spyware. For instance, if you have recently upgraded the Internet Explorer of your XP system to Internet Explorer 7, then a spyware infestation can generate the following error:
Waiting for res://ieframe.dll/dnserror.htm...
To repair this Windows DLL error, you must run an anti-spyware scan to search for the spyware that might be causing the problem and remove it from the system.
This error may also be generated if you try to visit a less secure site on the Internet using Internet Explorer 7. To resolve this issue, in the Internet Explorer window, open Internet Options > Security and disable the protected mode options.
This error may also display if have either the Zone Alarm or Kerio firewall configured on your system. To fix the error in this situation, you will have to uninstall the firewall causing the problem.
DLL files are used by Windows programs to perform various functions on the system. Overwriting of a newer DLL file, deletion of a DLL due to a program uninstall, faulty hardware, corrupt registry and malware infestation are some of the common causes of DLL errors. To prevent DLL errors, you must always keep your PC up-to-date with the latest updates released by Microsoft. You must also keep the definitions of your antivirus software and anti-spyware software updated and run regular scans on your system to keep it safe from malware infestation. Finally, you must download a reliable registry cleaner utility and regularly scan and remove errors from the registry to prevent it from getting damaged.