An "Authentication Error" on Dapple almost always means one of two things: you've clicked an expired sign-in link, or you're already signed into a different Dapple account in another tab or window. Sign out everywhere, request a fresh sign-in link, and try again in an incognito window if the issue persists.
Cause 1: Expired sign-in link
Dapple sends a unique, one-time magic link every time you request sign-in access. Each new link invalidates the previous one. If you click on an older email, you'll see an Authentication Error or a "link no longer valid" message.
Fix:
Request a new sign-in link from the Dapple sign-in page.
Open your inbox and click the link in the most recent email from Dapple — always the newest one.
Check spam or junk if the email doesn't show up within a minute or two.
If your email client collapses threaded emails, expand the full thread to see the latest message. Clicking the three dots in a collapsed thread usually reveals the most recent one.
Cause 2: Already signed into another account
If you're already signed into a different Dapple account in another browser tab, window, or device, trying to sign in to a second account triggers an Authentication Error.
Fix:
Check every open tab and browser window for an existing Dapple session.
Click your initials or profile picture (top-right of any Dapple page) and choose Sign out. This signs you out of all Dapple sessions across browsers.
Request a fresh sign-in link and click it.
Still seeing the error?
Clear your browser cache and cookies for dapplehq.com, then restart the browser and try again. If it still fails, open an incognito / private window — this rules out extensions and cached sessions. If none of that works, contact Dapple support with a screenshot of the error and the email address you're trying to sign in with.
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