Which MIME types are related to file extension ".identifier"?
The .identifier file extension is associated with 1 MIME types:
A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.
About .identifier Files
IDENTIFIER files are plain text files used to store Microsoft Zone Identifier data.
They contain simple metadata that marks a file's security zone. This data helps Windows decide if a file came from a trusted source or from the Internet.
- Main use: Flagging files downloaded from the web
- Security purpose: Indicating the trust level of the file
- Common content: Metadata like ZoneId values (e.g. ZoneId=3)
- Software: Openable with any basic text editor such as Notepad
According to FilExt.com, IDENTIFIER files serve as a security measure by marking the file's origin and potential risks.
Relationship between file extension and MIME type
A file extension is a suffix at the end of a filename that indicates what type of file it is. File extensions help both users and operating systems identify what application should be used to open the file.
File extensions are typically separated from the filename by a period (dot) and consist of 2-4 characters, though they can be longer. For example, in the filename "document.pdf", ".pdf" is the file extension.
File extensions are closely related to MIME types, as they both serve to identify the format of a file. However, while MIME types are used primarily by web browsers and servers, file extensions are used by operating systems and applications.
Associated MIME types
FAQs
What is an .identifier file?
An .identifier file is a plain text file containing Microsoft Zone Identifier metadata. It records the security zone from which a file was downloaded (such as the Internet) to help Windows determine if the file is safe to execute. The content typically includes lines like [ZoneTransfer] followed by a ZoneId number.
How do I open an .identifier file?
Because these files utilize the standard text/plain MIME type, you can view them with any text editor. Common built-in tools like Microsoft Notepad on Windows or TextEdit on macOS will open them instantly.
Is it safe to delete .identifier files?
Yes, it is generally safe to delete these files. Removing an .identifier file simply strips the "Mark of the Web" metadata from the associated file, which stops Windows from showing security warnings when you try to open that file.
What does ZoneId=3 mean inside the file?
Inside the file, the text ZoneId=3 specifically indicates that the original file was downloaded from the Internet. Other codes include ZoneId=1 for the local Intranet, ZoneId=2 for Trusted Sites, and ZoneId=4 for Restricted Sites.
Why did an .identifier file appear after extracting a ZIP?
This usually happens when using file compression or backup software that extracts Windows Alternate Data Streams (ADS) as separate physical files. Instead of hiding the metadata inside the file system, the software saved the security tag as a visible .identifier file.
Are .identifier files a virus?
No, .identifier files are not viruses; they are harmless text files used by the operating system to improve security. They help Windows identify potentially unsafe files downloaded from the web.
Can I convert an .identifier file to another format?
Since the file contains only simple text, you can save it as a .txt file, but converting it to formats like PDF or Word serves no practical purpose. The file is meant for system use, not for document creation.
General FAQ
What is a MIME type?
A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.
MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.
MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.
How do I find the MIME type for a file?
You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.
Why can one extension have multiple MIME types?
Different programs and historical usage may assign various MIME identifiers to the same file format. Listing them together helps maintain compatibility across tools.