When using a Mac, we may occasionally encounter error codes such as "The application can't be opened. - 10661". It may seem self-explanatory. It typically appears when you attempt to run specific software, especially software downloaded from a third-party source.
Why does it happen? How can I fix it? These are the questions you might be wondering right now. Don't worry, in this article, we'll explain it in detail and provide a complete troubleshooting guide.
- Table of contents
- About Mac Error Code 10661
- Preliminary Solutions for "The Application Can't Be Opened. - 10661" Error on Mac
- A Last Resort to Fix the 10661 Error on Mac
- Preventative Measures and Regular Maintenance Tips for Smooth App Operation on macOS
- Summary
About Mac Error Code 10661
It is curious for most people what 10661 means. Actually, it's also known as kLSExecutableIncorrectFormat. From the name, it is clear that the application's executable file format is incompatible with macOS. For example, you've mistakenly downloaded the Windows .exe installer. This error code can also be triggered in the following situations:
- 🧩 Application files corrupted or incomplete: It can occur due to an unexpected interruption in download, improper installation, or disk errors, causing some of the program's files to become corrupted or missing. It is similar to running an incorrectly formatted application, resulting in 10661 error on Mac.
- ⁉️ Apps from none Apple Store verified developers or the App Store: Compared to Microsoft, Apple employs stricter security measures to protect users from malware. Therefore, when the system detects an unsigned or suspicious app being launched, it is blocked by security protocols. By this, it may display the error "The application can't be opened. - 10661."
- ⛔ Apps do not work normally on the current macOS version: If the application was designed for an earlier macOS version, particularly if it uses deprecated frameworks or components, error code 10661 may occur during runtime. Besides, system updates that change core libraries or security policies can cause previously functioning applications to fail to launch.
- 🔒 Permissions Issues: macOS uses strict permissions to protect system integrity. The error may also occur if the account you're using lacks the necessary permissions to execute the application, such as when using guest authentication.
- ⚠️ Conflict with other applications: When an application is running, the system will load many files associated with it. If some of these files conflict with other applications, such as having the same file name, the application you want to launch will not be able to open.
Preliminary Solutions for "The Application Can't Be Opened. - 10661" Error on Mac
No one likes opening an app on their Mac only to find that it won't launch. Below are eight simple DIY troubleshooting methods that should get the app working again.
Method 1. Verify that the application's executable file is in a format supported by your Mac
macOS supports installer formats such as .dmg, .app, and .pkg. If you mistakenly download an installer package in another format and run it, you'll see the message "The application can't be opened. - 10661." In this case, you should download a Mac-compatible version from the developer's website.
Method 2: Redownload or update the app
After ruling out incorrect formatting, the most likely cause of the 10661 error on Mac is network congestion, which may have corrupted or incomplete app files, especially after an update. The solution is as follows:
Note: When an app isn't compatible with your macOS, all your efforts will be for nothing. In this case, please check the app's system requirements on the App Store or the official developer's website. It will give you more time to find alternatives, or you may need to consider upgrading or downgrading macOS if necessary.
- 🗃️ For apps downloaded from the App Store: please open the App Store and go to the "Updates" section to check if an update is available for the app causing error 10661. If not, uninstall it, then search for the app and install the latest version.
- 🌐 For apps downloaded from a third-party source: visit their official websites and download a version compatible with your macOS system. Then, uninstall the previous one and reinstall it with the new one.
Method 3. Restart your Mac
Sometimes, an application's temporary data may become corrupted, or its services may conflict with those of other apps running in the background, causing the 10661 error on Mac when the application is launched. To clear these issues, click the Apple icon in the menu and select Restart. After your Mac restarts, try to open the application again to see if the problem is resolved.
Method 4. Adjust security settings (applies only to third-party downloaded apps)
By default, your Mac only allows you to run apps downloaded from the App Store. When the system detects that the app is from a third-party source, it blocks the app from running and causes error 10661. Removing this restriction may resolve the issue.
- Click the Apple icon in the top left of the screen > select System Settings from the menu. On older versions of macOS, it should be "System Preferences."
- Select "Privacy & Security" in the left panel, then find the "Security" option on the right side of the page.
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Click the checkbox next to "App Store and identified developers" to ensure it's selected. When the confirmation dialog appears, enter your computer password and click "Unlock." If you see a message saying "[10661 Incorrect app name] was blocked from use because it is not from an identified developer. If software from developer "XXX" was blocked from loading, then please click "Open Anyway or Allow."
Tip: If you prefer a more straightforward way to adjust security settings, then type "sudo spctl --master-disable" in the Terminal and press Enter.
Method 5. Give the application full disk access permissions
When an application lacks full disk access permissions, the system will prevent it from launching, triggering errors such as "Cannot open application - 10661." Therefore, you can address this issue by adding the app to the "Full Disk Access" list.
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In the "Privacy & Security" menu, click "Full Disk Access". Scroll down to the bottom and click "+."
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In the dialog box that displayed, enter your Mac login password and click "Modify Settings."
- Select the application that displays error code 10331 and click "Open" in the bottom right corner of the page. Finally, relaunch the application to see if the issue has been resolved.
As with the previous solution, typing "bash diskutil resetUserPermissions /id -u" into Terminal is a shortcut.
Tip: Allowing the app to control your computer may also resolve error codes that appear when it runs. To do this, select "Accessibility" in step 2 and add it to the list using the steps above.
Method 6: Check and Repair Disk Errors
The key to the successful launch of an application is macOS's ability to read its data stored on the hard drive correctly, while the file system acts as the bridge between the app and the data on the hard drive. When the bridge(namely, the file system) is broken, the 10661 error on Mac may appear. Fortunately, "First Aid" in Disk Utility can sometimes resolve this issue. Here are the steps:
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Open Disk Utility by going to the Applications > Utilities folder.
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Select the system volume in the sidebar, then click the "First Aid" button in the toolbar.
- In the pop-up new window, confirm the action and click "Run." Once the check and repair process is completed, you can launch the application.
Method 7. Clear Application Cache and Preference Files
If you've used both Windows and Mac computers, you've likely noticed that apps on Mac are much faster. It is because macOS pre-stores frequently used data, such as cache and preference files, in the ~/Library/Caches/ folder for speedier loading. However, if these files become corrupted, the app may fail to launch and display the error code 10661. The following steps can help you clear these files, allowing the app to create new ones the next time you open it.
- Click Finder > Go > Go to Folder from the menu. You can also press "Shift + Command + G" to open the dialog directly.
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Enter "~/Library/Caches/" and click "Go."
- Find the folder named after the app or developer, such as "com.iBeesoft," and drag and drop it to the Trash icon on the dock.
- Go to "~/Library/Preferences/" and find the .plist file containing the app name or developer ID, such as "com.apple.iBeesoft," and delete it.
Once the application cache and preference files are deleted, you can relaunch the app to check whether error code 10661 has been resolved.
Method 8. Run Your Mac in Safe Mode
As mentioned earlier, software conflicts can also cause the "The application can't be opened. - 10661" error. Though it happens not so frequently, it can sometimes be. Therefore, running your Mac in Safe Mode is a good way to isolate the software conflict. In Safe Mode, macOS only loads the necessary components to ensure proper operation.
- After shutting down your Mac, press and hold the Power button until you see "Loading Startup Options," then release it. If your Mac has an Intel processor, hold down the Shift key immediately after starting up to log in.
- Select "Macintosh HD," then hold down Shift and click "Continue" to restart your Mac. When the login window pops up, you should see "Safe Boot" in the menu bar.
- Double-click the application icon that displays the 10661 error to launch it. If the issue persists, uninstalling any recently installed software may resolve the error. Otherwise, proceed to the next section.
A Last Resort to Fix the 10661 Error on Mac
If you've tried all the above-mentioned DIY methods and the problem remains unresolved, and there's no alternative for the app, send its log files to the developer for diagnosis. It is the last resort to fix the 10661 error. You can obtain the app's log files by following the steps below.
- Press "Command + Space" simultaneously. When you see the search box, type "Console" and press Enter.
- Enter the app name or error code 10661 in the search bar to filter for relevant log files.
- Finally, click "Share" in the toolbar to export and send to the developer.
Preventative Measures and Regular Maintenance Tips for Smooth App Operation on macOS
Error code 10661 in an application can be annoying, especially when you need it to perform the task at hand. If you don't want to see it again, review and follow the tips below.
- ✅ Use Apple-verified apps as much as possible, such as those downloaded only from the App Store.
- 🧼 Use tools like CleanMyMac to clean app caches regularly. Besides, you can use Disk Utility to check the health of your hard drive.
- ⚙️ Enable automatic updates. You can do this by going to System Preferences > Software Update and checking "Automatically keep my Mac up to date."
- 🔍 Use Activity Monitor to check CPU, memory, and disk usage. If you notice any services consuming unusually high resources, disable them.
Summary
It's frustrating to see the "The application can't be opened. - 10661" error message every time you try to open an app. Fortunately, there are multiple solutions to the annoying problem, and we've covered nine of them in this article that should help you get the app back online. Finally, to eliminate this error, take our advice and act promptly.