How do I set a default signature in Office 365?
From the File tab, click Options.
In the Mail section, click the Signatures…
In the Edit signature field, create your signature.
The first signature you create will be called “default.” To rename, click the Rename button and type a new name for the signature.
Why is my signature not showing in Outlook?
If you send a plain text email or your recipients can only receive plain text messages, your signature will not appear the same way it was formatted -- or it may not appear at all. You can create a text-only signature to use in plain text email messages.
How do I add an HTML signature to Outlook?
Open your signature file in a web browser (use Chrome for best results)
Copy the contents – Select and copy the whole content of the page.
Make a new signature in Outlook.
Add a new signature or select the one you want to overwrite.
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