Hi @Mick ,
I was trying to help someone today because the "Send" button in Outlook webmail was located at the bottom of the email window.
Actually the "Outlook" tag is for general issues about Outlook desktop client, so I am afraid little we can help regarding this particular query in Outlook webmail.
With this being said, could you clarify the type of the affected email account so that maybe I can help redirect your question to a more appropriate tag or forum? Is it an outlook.com/hotmail personal account accessed via https://outlook.live.com/, or it's a business Exchange account in your organization? If the latter, are you using Exchange Online or on-premises Exchange server in your organization?
Is this a suddenly occurred issue for this user? I mean, the Send button is at the top for her previously, right?
If possible, could you remove all personal information and share a screenshot of the issue so that our community members can understand better of the situation?
Besides, in case it's related to the internet browser, personally I'd suggest opening the Outlook webmail in private mode or switch to a different browser and see how it goes.
If it's an Exchange Online account, you can try switching the layout to check the result:
Additionally, as a temporary workaround for this user, she can consider using the shortcut keys to send out a message:
Keyboard shortcuts for Outlook-Web
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