The PSZ file extension represents Compressed PostScript files. These are PostScript files compressed using ZIP compression. Compressing PostScript files reduces their file size for faster transferring over the Internet. A 1MB PostScript file compresses to about 250KB. So transfer time is about one-fourth compared to uncompressed files.
To open a PSZ file, unzip it first. Then open the extracted PostScript file with any standard PS viewer. The default software to open PSZ files is WinZip. Corel acquired WinZip in 2006. And the first WinZip version for Mac appeared in 2010.
If a PSZ file does not open in Archive Utility on Mac, create a file association. This option is in file Properties menu. To associate PSZ files in Windows, add the extension in the Registry. Some tools to work with PSZ files are: PSZ File Opener, PSZ File Converter, PSZ File Viewer and PSZ File Editor.
When you double-click a PSZ file, Windows checks the extension. If it recognizes the extension, it opens the file in the associated program. If not, you get an error to select an app. This means Windows does not have a default program for PSZ files.
Many files like PSZ contain simple text data. But 236 extensions are assigned to PSZ files. Most are not compatible. You need different apps to open each type properly. The PSZ format was developed by an unknown creator. It was likely created with WinZip.
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