InstallShield installer archive

InstallShield installer archive is what we're calling the format of the  file included in many Windows software distributions that use the InstallShield installation software. It appears to be a general-purpose compressed archive format, though it's not clear whether it has been used in any other way.

Disambiguation
It is not to be confused with InstallShield CAB, InstallShield Z, or MS-DOS installation compression.

Discussion
Based on plausible but non-authoritative information, the 16-bit SETUP.EXE program detects the user's platform, and extracts the appropriate platform-specific installer programs from.

Identification
Files begin with bytes.

At offset 8 is the message " ".

Sample files

 * Examples of software with such a file:, ,

Links

 * FILExt page about the ??_ file extension pattern (Look for "InstallShield")