mime application/x-msdownload

The MIME Type application/x-msdownload is part of the ‘application’ category and it is commonly used to indicate the encoding for the DLL file type when such a file is present within a message. This MIME Type in general describes executable and/or system files that are associated with the Windows and OS2 platforms and is also used for the EXE file type. Due to their executable nature, these file types are often put under block or restricted lists to avoid contracting an infection from these files. Most email services will block these files from being sent over their networks.

The DLL and the EXE file types have many characteristics in common. Both are likely to have code, data and resource in any of the possible combinations. While DLL is not directly executable, it is an active file that can store malicious code inside that can then damage a system. DLL files are often made for resource sharing actions between various components of a program or an OS like Windows XP. A DLL file is described as a ‘dynamic link library’.

The application/x-msdownload MIME Type may be replaced by application/octet-stream or application/x-msdos-program under certain circumstances.