Hi @MABIALA, Ludovic
Thank you for posting your question in the Microsoft Q&A forum.
I understand that you’re experiencing an issue where the Send button is grayed out when you try to send a draft email.
If you’re unable to send email because a message with a large attachment is stuck in your Outbox, try opening the Outbox and either deleting the message or reducing the attachment size before sending again.
This issue can also occur if Outlook starts in a limited mode, which sometimes happens after clicking an email link. Closing Outlook completely and reopening it directly from the Start Menu usually resolves this.
Additionally, check whether Outlook is set to Work Offline. To turn it off, go to Send/Receive > Work Offline.
If the issue continues, make sure your email account is correctly configured. Go to File > Info > Account Settings > Account Settings, and verify that your email account appears on the Email tab.
I’ve also found a helpful article you may want to refer to:
I can't send or receive messages in Outlook - Microsoft Support
To better assist you, could you please provide a bit more information on the following:
Can you try creating a new test email to see if the issue also occurs with other draft mails?
Is the Send button completely grayed out, or does it appear clickable but nothing happens when you select it?
Could you share your current Classic Outlook build and version?
I hope this helps.
Please feel free to correct me if I misunderstood your request. If you have any additional concerns, feel free to comment below. I would be more than happy to assist.
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