Notes about the IPSW file extension:
Incorrect file associations could be the result of underlying issues within your PC system. As such it is highly recommended to scan your PC for invalid registry entries
, unused processes and other unfavourable system settings to identify slowdown issues.
The IPSW file type is primarily associated with 'iPhone/iPod' by Apple Inc.. This is a firmware update file for the iPhone. The file is a renamed .ZIP file. If you unZIP it you will see a file called MANIFEST.PLIST and a file without an extension but with a version number in the name, e.g., Firmware-14.5.3. This file is the firmware image.