An annoying error that some Mac users may encounter is known as 'Error Code 10826.' It manifests by preventing users from opening applications, documents, or files on their Mac systems. Instead, a pop-up is triggered stating that 'The application can't be opened -10826.' The reasons for this particular issue can vary depending on the system so finding the right solution may need trying several different suggestions.
Update the MacOS
If you have noticed that the error started appearing after a major MacOS update, then it may have been caused by software incompatibility or a bug introduced with the update. Users have a couple of choices - they can wait for a new system update to be released that will hopefully fix the issue or try to restore their Mac computers to a state before the update was installed via MacOS's Time Machine.
Check for Intruder Applications
The 'Error Code 10826' problem also could be caused by intrusive applications known as PUPs (Potentially Unwanted Programs) or malware threats. PUPs are often able to sneak their way to the system without being noticed by users, thanks to the underhanded distribution tactics they employ. For example, bundling the intruder application as a preselected choice inside the installation settings of a more popular software product. After a successful invasion, they may perform numerous intrusive actions including spying on the user's browsing activities. To check if such applications are lurking on your Mac, do a thorough scan with a reputable security solution.
Boot the Mac in Safe Mode
Starting your Mac in Safe Mode could also help. Doing so, will force the system to verify the startup disk and then repair any detected issues. It also ensures that the Mac will be running with the minimum required apps and features thus excluding any third-party kernel extensions, Startup items, Login items and more. This is a good way to test if the error is caused by a software incompatibility, a PUP that is still present on the system or a malware threat. Depending on your specific Mac model the method for starting Safe Mode differs:
For Intel-based Mac systems:
- Shut down the Mac and wait for approximately 10 seconds.
- Start the Mac back up and immediately press and hold the Shift key on your keyboard.
- When the login window appears, release the Shift key.
For Mac systems with Apple silicon:
- Shut down the Mac and wait for around 10 seconds.
- Press the power button and hold it until the startup options window appears.
- Select a startup disk.
- While holding the Shift key on your keyboard, click the 'Continue in Safe Mode' option. Release the Shift key afterward.