Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Protect your iPhone with Mobile Active Defense
Despite its reliability, your iPhone’s iOS can be harmed by an ordinary email message, as it can contain MS Office or Adobe documents as attachments, or links to malicious websites. Mobile Active Defense (MAD) is an e-mail security service for smartphones, designed to protect them from all possible threats coming from e-mails. MAD is compatible both with Mac OS and Windows, and can be used with desktop e-mail clients as well.
The app that costs $17, with a 30-day trial period, enables you to create a special e-mail account squeezed between your existing account and your phone’s Mail app. It will filter the incoming mail and put away with messages it considers potentially dangerous.
MAD offers three levels of e-mail security service:
We tested only the Consumer level, so we hope that other two levels offer more advanced functionality.
How it Works
Once you’ve installed the app, you should go to your Mail settings and disable your regular e-mail account for the new protected account to work. This account will be created automatically when the installation is completed.
MAD will check your regular account, download the incoming messages to its servers, analyze them, and transfer those considered to be safe to your protected account. However, it will take more time than receiving the mail at your regular account; the delay may reach up to ten minutes!
In addition, MAD’s Consumer security level has some other drawbacks. For example, it does not filter e-mails with the attached .exe, .com, .dll and other ‘suspicious’ files, as compared with Gmail. In addition, it lacks reports on the filtering activities; the user isn’t aware which e-mails it considers malicious. Finally, the user can control only the maximum size of e-mail attachments allowed; it would be great to add more customizable features.
Pros: Three levels of security. Reasonable price. 30-day trial period. Customizable size of allowed e-mail attachments.
Cons: Large delay when receiving the mail. Poor filtering of potentially dangerous attachments. Lack of reporting and customization.
Mac Reviews Rating: 2.5/5