File Extension DLL

File Extension DLL

DLL means "Dynamic Link Library" or "Application Extension" and it is used by Microsoft Windows applications to store executable code which could be shared between several applications. Also Microsoft Windows uses DLL files to store executable code for different windows components (graphical engine, networking, printing, etc.).

DLL is probably the most frequent executable file extension on your computer (others include EXE, SYS, COM and DRV). You can see the most of them in your C:\Windows\System32 or C:\WINNT\System32 folders. But each application also stores lots of DLL files in its own folders.

If you have an unknown file and you think this file is a DLL you can check it using following methods:

• Open file in text editor (notepad or more advanced one) and see if first letters of file are MZ. MZ means Mark Zbikowski - developer and architect at Microsoft who introduced this file type. MZ at the beginning of the file means that this file is executable and it is either DLL or EXE
• Another typical phrase you can find inside DLL file is "This program cannot be run in DOS mode." which is a message produced by Windows when you're trying to run DLL from DOS console.

Applications capable of opening File Extension DLL

• Microsoft Visual Studio. It is capable of opening DLL file and viewing and editing certain sections of it like textual resources, icons, messages, etc.
• Microsoft Disassembler. It is part of visual studio but it will allow you to view DLL file in great details. It will decompile DLL from binary code to assembly instructions which are much easier to read than binary code.

Similar file extensions

• File Extension EXE - executable code for applications
• File Extension SYS - executable operating system code
• File Extension COM - old DOS style format for executable code
• File Extension DRV - executable code for drivers
• File Extension SCR - executable code for screen savers

Get more information about File Extension DLL.

If you are not able to open file with certain file extension make sure to check if extension for the file is correct. It is possible that information in the file doesn't match file extension.