The ZIP format is an archive file format that supports lossless data compression. Like other archive formats, it compiles one or more files and/or folders into a single file for easy transport and compression. However, some users on Mac OS encounter an error when attempting to unzip by double-clicking the ZIP file. They receive an error message stating Unable to expand filename.zip (Error 1 – Operation not permitted.), which appears in the Archive Utility dialog.
After investigating this particular issue through various user reports and the commonly used repair strategies for troubleshooting, we’ve identified several scenarios known to trigger this error message:
- The downloaded file is corrupted – When downloading files via a browser on Mac OS, the file may not download correctly and completely if the website is closed before completing the download. This can result in you being unable to open the ZIP file despite its presence in the Downloads folder. To resolve this issue, re-download the file without closing the browser or use the Terminal to download it.
- ZIP file containing a very large file – The error may also occur when decompressing a very large file. Several users have resolved this by using the Terminal with the unzip command instead of the Archive Utility, which does not support unzipping large files.
- Permissions on ZIP files – Sometimes, you may not have the correct permissions for reading/writing the directory of the ZIP file, which can cause this error. If this is the case, you can resolve the issue by using third-party software to unzip the files.
If you’re actively seeking solutions to this error which prevents you from accessing ZIP files, this article offers a collection of troubleshooting steps. Below, you’ll find methods that other users have successfully employed to fix the problem.
Method 1: Unzip File Using Terminal
When simply double-clicking the ZIP file does not work, you can try unzipping the files using Terminal. Sometimes large files cannot be decompressed with Archive Utility and thus require the Terminal. The command “unzip” is used in Terminal for ZIP files. This command sends the file to the user account folder.
- Hold Command and press Space to open Spotlight. Type Terminal, search it and press Enter.
- Use the unzip command on your ZIP file.
(Drag and drop the ZIP file to paste the directory as well).
- Press Enter to start unzipping.
- If there are any errors like “No such directory” or “Cannot find,” manually use the “cd” command to navigate to the directory and unzip from there, like so:
cd Desktop unzip timer.zip
If this method doesn’t resolve the issue, try the next approach detailed below.
Method 2: Using a Decompression Utility Software
At times, permission issues or difficulties with opening ZIP files normally can occur. However, the App Store and various online sources offer utility software that can help with unzipping ZIP files trouble-free. Download the Stuffit Expander from the Mac App Store and use it to unzip your files. This software has assisted users who were unable to unzip files even with Terminal.
- Click the Mac App Store icon in the Dock.
- Search for “Stuffit Expander” in the App Store.
- Click Get followed by Install to download and install the application on your Mac OS.
- Once installed, open the application either directly or by searching for “Stuffit Expander” through Spotlight (Command + Space).
- Click on the application’s Stuffit Expander Icon.
- Locate and select the ZIP file you wish to unzip.
- Choose the destination folder to unzip the file to.
- The application will then unzip the compressed file for you.