Outlook wont send emails from mobile devices but will from desktop

Hello David Chapman,

Thank you for posting to Microsoft Q&A. 

I can certainly understand how frustrating it is when your email works perfectly on your desktop but leaves you disconnected while you're on the go. It is quite common for the sync relationship between a mobile device and the server to need a "refresh" after an update or a connection glitch. 

To get your iOS device sending emails again, please try these steps in order: 

1. Reset Your Account 

• Open the Outlook app on your iOS device. 
• Tap your profile icon in the top left, then tap the Settings (gear icon) at the bottom. 
• In Accounts, select the email account that isn't sending. 
• Scroll down and tap Reset Account. The app will restart and attempt to resync your folders. 

2. Remove and Re-add the Account 

If a reset doesn't work, a clean reconnection is the most effective fix. 

• Delete the Account: In the same Settings menu, select your email account and tap Delete Account 
• Restart Your Device 
• Add Account Again: Open Outlook, select Add Account, and enter your credentials. 

Testing the connection after a fresh install and a device restart usually clears up any communication blocks between iOS and the Outlook servers. Please let me know if you're still unable to send after trying these steps! 

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