How to fix [5ssai]

Hi @Rosemarie Rogerson 
Thanks for reaching out to the Microsoft Q&A forum.  
I understand how inconvenient and frustrating it can be when you're unable to add your account to Outlook on a new mobile device due to the error message 5ssai. 

Based on my research, the 5ssai error message typically indicates an issue related to account authentication or security settings. While the cause may vary from case to case, several users have shared common troubleshooting steps that may help resolve the issue: 

1.Clear cache Outlook app 

 Go to: Settings > Apps > App Management > Outlook > Storage Usage 

Note: The exact path may vary slightly depending on your device, but the general steps should be similar. 

2.Uninstall and reinstall the Outlook app from the Play Store 

If the issue persists, may I kindly clarify the following: 

• Is your school account set up to use Microsoft Authenticator as the authentication method? 
• Aside from being unable to add your account to the Outlook mobile app on your new phone, are you able to sign in to Outlook on the web using a browser on the same device? 

Additionally, I came across similar threads that may offer helpful insights: 

• Can't get email to work on smartphone - Microsoft Q&A 
• 'Something went wrong. 5ssai. - Microsoft Q&A 

Please know that while our initial response might not resolve the issue right away, your input is incredibly valuable. With a bit more detail, we’ll work together to find the best solution for you. 

I look forward to your updates. 

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