Several Outlook users, on different forums, have reported encountering the error “OST file cannot be opened,” when trying to open the application or sending ...

You can fix the error by updating the app or adjusting your Mac's security settings. If the app is not verified, try downloading it again using Safari and follow the ...

Outlook is the Office suite’s email and Callender software that provides many features. Although it started off as an email client (which it still is), people use ...

Apple’s Gatekeeper technology protects your device from harmful viruses. When the security software detects that the app is downloaded from outside the app store or an unidentified developer, it ...

Learn to install unsigned Mac apps safely by updating, finding alternatives, or adjusting security settings Reviewed by Jessica Kormos You can fix the error by ...