Outgoing email gets stuck in the outbox

Hi @James Seery

I’m sorry that outgoing emails keep getting stuck in the Outbox on both your iMac and MacBook Pro.

Since you are using New Outlook for Mac and the issue occurs on both devices, please first sign in to your email account through webmail and try sending a small test message without attachments. If the message also cannot be sent there, check whether your mailbox storage is full and contact your email provider, as this may be an account or mail-server issue.

If sending from webmail works, please update Outlook by selecting Help > Check for Updates, restart both Macs, then delete the stuck message from the Outbox or move it to Drafts and resend it without attachments. Please note that the Online/Offline toggle is not available in New Outlook for Mac.

If the issue continues, please let us know which email provider you use and whether Outlook displays any message when the email becomes stuck.

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