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Polaris Express Docs

I'm stuck in a sign-in loop

If the ExpresScan app keeps sending you back to the welcome screen after you scan your card or tap a sign-in email, this page walks you through getting unstuck. You’ll check a few things on your phone, then try sign-in again.

Before you start

Section titled “Before you start”
  • The iPhone you’re trying to sign in on, unlocked.
  • The most recent version of the ExpresScan app installed from the App Store.
  • Either your physical EV card (for the QR scan flow) or the sign-in email from Polaris Express (for the magic link flow).

Steps

Section titled “Steps”

Goal Recover from a sign-in loop on iOS

Time~5 min

  1. Confirm you're online

    Open Safari and load any website. If pages don’t load, the app can’t reach the sign-in server either, and the welcome screen is the only place it can land.

    Switch to a working Wi-Fi network or move somewhere with a stronger cellular signal, then reopen ExpresScan.

    The welcome screen is where you land whenever the app can't complete sign-in.

  2. Force-close and reopen the app

    Swipe up from the bottom of the screen and pause in the middle to open the app switcher. Find ExpresScan and swipe its card up to close it.

    Tap the ExpresScan icon on your home screen to reopen it. The app checks for a stored sign-in each time it launches, so a clean restart clears any half-finished attempt from the previous run.

  3. Try the sign-in link from the same device

    The magic-email link and the QR-code link on your EV card both need to open inside the ExpresScan app on your iPhone — not in a desktop browser, and not on a different phone.

    • For email sign-in: open the email on the iPhone with ExpresScan installed, then tap the link.
    • For QR sign-in: open the iPhone Camera app, point it at the code on your EV card, and tap the banner that appears.

    If the link opens in Safari and shows a web page instead of bouncing into the app, iOS has lost the association between the link and the app. Reinstalling the app (next step) fixes this.

  4. Reinstall the app as a last resort

    Press and hold the ExpresScan icon, choose Remove App, then Delete App. Reinstall it from the App Store and try your sign-in link again.

Verify

Section titled “Verify”

You’re past the loop when the app shows your home screen with the scan button instead of the welcome screen. If you signed in with your EV card, you’ll also see a brief “Signing you in…” screen first.

Once sign-in completes, the app lands on your home screen instead of bouncing back to welcome.

Troubleshooting

Section titled “Troubleshooting”

The progress screen says “Couldn’t sign in. Try scanning again.” The sign-in attempt reached the server but didn’t complete. Tap Try again, which returns you to the welcome screen, then scan your EV card once more. If it fails twice in a row, switch to the magic-email link instead.

The magic-email link opens Safari instead of the app. iOS occasionally drops the link-to-app association after an OS update. Delete and reinstall ExpresScan, then tap the link again from the Mail app on the same iPhone.

I see an offline overlay I can’t dismiss. The app has detected that it can’t reach Polaris Express. It will retry on its own — the overlay closes itself once the connection is back. Check your Wi-Fi or cellular signal in the meantime.

None of this worked. Contact Polaris Express support with the email address on your account and the approximate time you last tried to sign in. Support can check the server-side log for your sign-in attempts.

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