Outlook won't send from my mobile phone but will receive emails

Hi @Mitch Turner, 

I hope you’re doing well.

Since sending works on the laptop, your account and mailbox are likely functioning correctly. The issue is most commonly related to the Outlook mobile app, network conditions on the phone, or a sign-in/security token needing refresh. 

To better assist you, could you please provide the following: 

• When you try to send an email, do you see any specific error message? If yes, please share a screenshot of the error. 
• Does the email stay in the Outbox (or show “Sending…”) or does it disappear after you tap Send? 
• Have you recently changed your password or enabled/updated Multi-Factor Authentication (MFA)? 

Once I have this information, I’ll be better positioned to guide you through the next steps.  

Also, since you haven’t specified your account type (work/school vs. personal), I may not be able to provide an exact solution yet. Assuming you’re using a work/school account, please try the steps below. If you’re using a personal account, please let me know and I’ll tailor the guidance for that scenario.  
1/ Check the Outbox  

• Open Outlook > Outbox. 
• If messages are stuck there, try deleting the stuck item and sending a simple test email (no attachment) to confirm sending works. 
• If you need to resend the same email, try removing large attachments or reducing attachment size. 

2/ Switch networks & disable VPN (if applicable) 

• Try sending using a different Wi‑Fi network or mobile data (4G/5G). 
• If you use a VPN, please disable it temporarily and test sending again. Some networks/VPNs can block or interrupt outbound mail traffic. 

3/ Refresh the Outlook mobile sign-in 

• In Outlook on your Android device, go to Settings > select your email account > Reset Account. This forces the app to restart and refresh/resync local data for that account.  
• After Outlook reopens, try sending a short test email (no attachment). 
• If the issue persists, please remove the account and add it back in Outlook (Settings > select account > Remove/Delete account > Add Account), then complete sign-in/MFA prompts if shown 

Additionally, ensure Outlook is updated from the Google Play Store. 

Then restart your phone and try sending again. 

4/ Clear Outlook cache (Android) 

• Android Settings > Apps > Outlook > Storage > Clear cache. 
• (If the issue persists, you can consider “Clear data” later, but clearing cache is the safer first step.) 

5/ Allow Outlook to run in the background 

• Battery Optimization: set Outlook to Unrestricted/Not optimized. 
• Ensure Background Data is allowed and Data Saver isn’t restricting Outlook. 
• These settings can prevent messages from finishing the send process. 

If this is a work account and your organization uses security policies (e.g., device compliance/MDM), you may also need to verify whether your device meets the required security/compliance settings. 

Additional guidance: How to Fix Outlook Not Working on Android 

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I hope this information is helpful. Should you have any further questions or need additional assistance, please feel free to comment below.

Thank you for your patience and I look forward to your update. 

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