.ocx Windows or EFI program
Programs & libraries
| MIME type | application/vnd.microsoft.portable-executable |
|---|---|
| Description | Windows or EFI program |
| Acronym | EFI – Extensible Firmware Interface |
| Category | Programs & libraries |
| Signature (magic bytes) | 4D 5A (MZ) |
| Based on | application/x-msdownload |
| Other extensions | .cpl, .dll, .drv, .efi, .exe, .lib, .scr, .sys |
Frequently asked questions
What is a .ocx file?
A .ocx file is a “Windows or EFI program” (MIME type application/vnd.microsoft.portable-executable). EFI stands for Extensible Firmware Interface.
How do I open a .ocx file?
This is executable code or a library. Only open such files from trusted sources; to inspect them, use tools such as file, objdump or a hex editor.
How can you tell a genuine .ocx file?
By the bytes at the start of the file, the signature (magic bytes): 4D 5A (MZ). On Linux and macOS, file --mime-type example.ocx checks the real type regardless of the extension.
Which format is .ocx based on?
Technically a .ocx file is a subtype of “Windows or DOS program” (application/x-msdownload), so programs for that base format can often read it too.
Which MIME type belongs to .ocx?
The MIME type is application/vnd.microsoft.portable-executable. In the Apache web server: AddType application/vnd.microsoft.portable-executable .ocx; in nginx: types { application/vnd.microsoft.portable-executable ocx; }.