Match the symptom.
A logo that disappears after sending is different from a signature that never appears in the compose window. Start with the closest symptom, then change one thing at a time.
Visible in preview02
Missing after sending03
Check source + settings
| Symptom | Possible cause | Next check |
|---|---|---|
| The whole signature is absent | No default selected, wrong sending account or a reply-specific setting. | Check the selected account and new-message/reply defaults in your email settings. |
| Text arrives, but an image is missing | Remote images are blocked or the image source cannot be reached. | Check recipient image settings and open the image URL separately. |
| A local upload works only in the preview | The email app removed or did not preserve the embedded data URL. | Use a durable public HTTPS URL or the email app’s own image tool. |
| The URL asks you to sign in | The source is private or is a sharing page rather than a direct image. | Use a direct image address that is accessible without signing in. |
| An image stops working later | The file moved, access changed or a temporary URL expired. | Check the original address and choose a stable source you control. |
Where does the image live?
A public HTTPS image URL lets the email app retrieve the image from a server. That server must keep the file available; a link that expires or needs a login is not a durable source.
A file selected from your device is embedded in your signature document as a data URL. The preview can display it, but an email service may preserve it, rehost it or remove it. A successful preview does not prove successful delivery.
Check the public image address.
- Copy the image’s HTTPS address, rather than a link to a gallery or file-sharing page.
- Open it in a private browser window where you are not signed in. It should show the image directly.
- Check that the address has no temporary access requirement and that your host allows other people to retrieve it.
- Replace the image address in the editor, copy the signature again and update the installed version.
This check confirms public access at that moment. Some hosts still restrict requests from email services, so send a test as well. Use only images you are comfortable making publicly accessible.
Blocked or broken?
If the image address works but a received message hides it, the recipient’s app may be choosing not to load remote images. That choice belongs to the recipient; rebuilding the signature will not override it.
In Gmail on a computer, image preferences are under Settings → See all settings → Images. Gmail may also ask before showing images in a message it considers suspicious. Follow Google’s current image-setting guidance and load images only when you trust the message.
A broken source needs fixing at the host or replacing in the signature. Useful text beside your logo helps the reader in either situation.
Try your email app’s image tool.
Where your email app supports it, inserting the logo directly in its signature settings may be an alternative to a pasted local upload. Check the app’s own instructions and test the result; its storage and delivery behavior are controlled by that provider.
Google’s Gmail signature instructions describe adding an image in the signature field. For Mac, use Apple’s Mail signature instructions. Our Install guide also links to the current Outlook instructions.
Test a new message and a reply.
Send to another account, rather than relying on the compose window. Check a new message and a reply on desktop and a phone. Confirm the image, written contact details and links, and check that the signature remains useful with images hidden.
If the problem remains, contact us with your email app, whether the issue appears before or after sending, and the checks you tried. Do not send passwords or private account links.