I recently updated to macOS 15.4. When I try to open a simple text file with an .srt extension, I get the following warning: “Apple could not verify that 'xxxx. srt' is free of malware that may harm your Mac or compromise your privacy.” - Apple Community
After updating macOS, many users have experienced issues where the system refuses to open certain files. In some cases, a security warning appears; in others, files fail to open without any error message or notification.
Whether you've upgraded to version 15.4 or another release and are struggling to find a solution, you've come to the right place. In the following sections, we'll provide you with detailed fixes to resolve this issue.
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Right-click to bypass the security warning
If macOS displays a warning like: “Apple cannot verify that this file is free of malware...”, you can manually override this restriction.
However, you can only do this for files that macOS allows a limited override for (usually files downloaded from the internet).
Here is how to do it:
- Locate the file (e.g., filename.srt) in Finder.
- Right-click (or Control-click) on the file.
- Choose “Open” from the context menu.
- At this time, a similar warning will appear, but you'll have the option to click “Open” to confirm.
Now, you can try to open the file again. This tells macOS you trust the file and want to run it anyway. This is a quick and easy fix, but you'll need to repeat this process for each file individually.
Allow the app or file in System Settings
macOS 15.4 introduces stricter security verification, especially for apps or files from unidentified developers. If macOS can't verify the developer or confirm that the file is safe, it will block access by default.
This approach is much safer than disabling system security entirely, and it eliminates the need to right-click and choose "Open" every time.
Here is how to do it:
- Go to System Settings → Privacy & Security.
- Scroll down to the Security section. If the file was recently blocked, you'll see a message like: “'filename' was blocked from use because it is not from an identified developer.”
- Click “Allow Anyway.”
- Try opening the file again.
Note: This option only appears if you recently attempted to open the blocked file.
Use iBoysoft DiskGeeker for Mac to free up disk space
When you open certain files on your Mac, such as large text documents, media files, or compressed archives, the system creates temporary cache files to support the operation. If there's not enough free disk space, macOS may fail to allocate the necessary resources, causing the file to fail to open.
In addition, the apps required to open these files, like QuickTime, Preview, or even Finder, also need a certain amount of available disk space to function properly. When your memory and cache are full, these apps may become unresponsive or fail to launch correctly.
To check your available storage, go to Apple Menu > About This Mac > Storage. It's recommended to maintain at least 10–15% of free disk space to ensure macOS runs smoothly, especially during system updates or when working with large files.
If there is not enough disk space, you can manually delete files no longer needed. Alternatively, you can try iBoysoft DiskGeeker for Mac to save time and avoid guesswork.
This feature-rich disk management tool can help you analyze how your disk space is being used. It also includes AI-powered content analysis, which helps identify file types and avoid accidentally deleting important data.
Share iBoysoft DiskGeeker for Mac to help more people free up disk space!
Reset Gatekeeper
Gatekeeper is a built-in macOS security feature designed to prevent unsigned or unverified applications from running, helping protect users from potential malware.
However, after upgrading the system (such as updating to macOS Sequoia 15.4), Gatekeeper may occasionally misidentify safe files or apps as harmful, resulting in them being blocked from opening.
To resolve this, you can reset Gatekeeper via Terminal to refresh its security settings.
- Open the Terminal.
- Enter the following command to disable Gatekeeper, then press Enter (you may be prompted to enter your password):sudo spctl --master-disable
- Re-enable Gatekeeper by running:sudo spctl --master-enable
Running these commands resets Gatekeeper's configuration and clears any incorrect flags, allowing previously blocked files to open properly.
Note: Be sure to re-enable Gatekeeper after the reset. Leaving it disabled may expose your Mac to security risks by allowing all applications to run without verification.
Boot into Safe Mode or Use Another User Account
In some cases, macOS may refuse to open files due to issues with the current user's environment, such as corrupted user settings, cached files, or third-party extensions.
Booting into Safe Mode or logging in with a different user account can help determine if the problem is isolated to your current user profile.
Boot into Safe Mode
- Shut down your Mac.
- Restart and immediately press and hold the Shift key (on Intel Macs) or press and hold the power button (on Apple Silicon Macs) until you see startup options.
- Select your startup disk, then hold Shift and click “Continue in Safe Mode.”
- Log in and try opening the file again.
In Safe Mode, certain system features and third-party drivers are disabled, so you may notice reduced performance or limited functionality.
Log In with Another User Account
- Go to System Settings > Users & Groups.
- Click the Add Account button in the lower-left corner to create a standard or administrator account.
- Log out of your current account and log in with the new one.
- Try opening the file again.
If the file opens successfully in the new account, this indicates the issue lies within the original user environment, such as login items, preference settings, or permission conflicts.
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