Here's the short answer: your email client probably isn't broken. If a logo or photo in your signature shows up as a blank box, a small broken-image icon, or nothing at all, the cause is almost always how that image got into your signature in the first place — not a quirk of Gmail, Outlook, or Apple Mail specifically. Every major client treats images the same cautious way: block by default, ask permission, or refuse anything that looks like a locally-saved file pretending to be a photo. Once you know which of those three things is happening, the fix takes about two minutes.
Why is my signature image not showing at all?
Most of the time, it's not that the image failed to load — it's that the image was never really there. If you built your signature by copying a logo out of a folder or pasting from a Word document, what you actually pasted was a reference to a file on your own computer. That reference means nothing once the email leaves your outbox. The recipient's inbox has no way to reach your hard drive, so it shows the universal broken-image icon instead.
This one cause — a local file path standing in for a real image — accounts for more 'my logo disappeared' reports than every email client quirk combined. It's also invisible from your side, because your own machine can still find the file when you check. The problem only shows up on the receiving end, which is exactly why it's confusing to diagnose.
Why is my logo missing specifically in Gmail?
Gmail adds two of its own rules on top of the general problem. First, it doesn't reliably render images embedded directly in the HTML as encoded text (the technical term is base64) — Gmail's web interface has a history of stripping or refusing these, partly because that encoding method has been used to hide malicious content in the past. If a signature tool built your logo this way, Gmail may simply drop it.
Second, Gmail blocks images hosted on an insecure connection — a link starting with http:// instead of https://. Google is direct about this in its own guidance: it won't load a source it can't verify as secure, to protect recipients from spoofed content. If your logo's hosting link isn't on HTTPS, Gmail treats it as absent rather than broken.
Why is my logo missing specifically in Outlook?
Outlook's most common cause isn't really a bug — it's a setting working exactly as designed. Outlook blocks automatic downloading of external images by default, on every account, as a privacy and security measure. Instead of your logo, the recipient sees a placeholder and a prompt asking them to click to download pictures.
That part is out of your control on the sending side; it's the recipient's client configuration, not your signature. What you can control is making sure the image is worth that click — a properly hosted, correctly-sized logo that appears cleanly the moment someone allows images, rather than one that's still broken even after they do. If it's still broken after 'download pictures' is clicked, that's the local-file-path problem above, not this setting.
When more than one cause is stacked together
- Local file path (from pasting a Word or Google Docs signature): breaks in every client, every time — including your own test send.
- Base64-encoded image: breaks specifically in Gmail's web interface, often still works in Outlook or Apple Mail.
- Non-HTTPS hosting link: breaks in Gmail specifically; may show a security warning elsewhere.
- Recipient's 'download pictures' setting off: breaks temporarily in Outlook and some corporate inboxes, resolves once they click to allow it.
- Corporate firewall blocking the specific image host: breaks only for recipients on that network — the hardest one to diagnose, because it looks fine to everyone else, including you.
The fix that holds across all three
Every cause above points to the same fix: the image needs to live on a stable, always-on web address, delivered over HTTPS, and referenced by that address — never pasted as a local file, never encoded as text. That's the entire difference between a signature that survives the trip to someone else's inbox and one that doesn't.
It's also why 'it looked fine when I sent it to myself' isn't proof of anything. Your own machine can paper over a local-file reference in ways a stranger's inbox can't. The real test is sending to an address you don't control — a personal account, a colleague on a different client — and checking what actually shows up there.
When you upload a logo in Signoff Craft, it's hosted at a stable link the moment you finish — that's what your signature carries, not a copy of the file itself, not encoded text, not a shortcut back to your desktop. It's an unglamorous fix, and it's the one that actually holds.
A 60-second way to check which cause you have
- Send the signature to an address on a different provider than the one you're using — Gmail to Outlook, or the reverse.
- Broken there too, even though it looked fine in your own outbox: it's a local file path. Rebuild the logo as a hosted upload, not a paste.
- Broken only in Gmail: suspect base64 encoding or a non-HTTPS hosting link.
- Broken only until the recipient clicks 'download pictures': that's Outlook's default setting, not your signature.
- Broken only for one recipient, on their work network: likely a firewall blocking the image host — worth a note to their IT team, but not something you can fix from your side.
Fix it once, not every time
None of this is really a Gmail problem or an Outlook problem — it's an image-hosting problem that shows up differently depending on which client someone's using. Once the logo is on a stable, HTTPS-hosted link instead of a local file or encoded text, it tends to stay fixed. You won't need to re-diagnose it every time someone mentions a blank box in their reply.
If your current signature has been quietly breaking for people you can't see, rebuild it in Signoff Craft — upload the logo once, and the hosted link is handled for you from there.
Create your signature
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