Opening SIG files

Have a problem opening a .SIG file? We collect information about file formats and can explain what SIG files are. Additionally we recommend software suitable for opening or converting such files.

What is the .SIG file type?

Short for 'Signature,' the .sig extension is primarily used to denote the generic Detached Digital Signature (SIG) file type. A digital signature is a unique sequence of characters generated against a given block of digital data and used to prove authenticity and/or authorship of such data.

Digital signatures are generated with the use of strong asymmetric cryptography algorithms (RSA, DSA, 3DES, Blowfish, etc.) and widely employed to sign financial, government, personal, and other digital correspondence/documents that must remain tamper- and forge-proof.

A digital signature can be either attached to the file being signed, or generated as a detached signature file (.sig) that only contains the body of a digital signature created against another file. For verification, both files (the signed file and the detached signature file) must be present in the same directory. Detached digital signatures (.sig) are often distributed together with software installation packages, disk images, etc. for integrity verification purposes.

Besides digital signatures, the .sig extension can also be assigned to message signature files used by several messaging applications. Such .sig files are plaintext files that only contain a small text (or ASCII art) block, to be automatically appended to each outgoing message as a personal signature of its sender. Such message signature files serve an entirely different purpose and are not to be confused with digital signatures.

Lastly, the .sig extension has an association with the Broderbund Print Shop Sign (SIG) file format and type. Broderbund develops and provides a variety of design- and printing-related software. SIG is a proprietary binary file format used by Broderbund applications (mainly, The Print Shop and PrintMaster) to store bitmap images for poster or sign projects. SIG files can be opened/imported by other Broderbund titles.

Software to open or convert SIG files

You can open SIG files with the following programs:
Delfino G3
Delfino G3 by Wizvera
The Print Shop
The Print Shop by Broderbund Software
Symantec Encryption Desktop
Symantec Encryption Desktop by Symantec Corporation
FileViewPro by Solvusoft Corporation

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