USPS Informed Delivery can’t sign in (2026): how to break the “Authentication Failed” + MFA loop and get access back
If you rely on USPS Informed Delivery to preview your incoming mail or manage packages, being locked out is more than annoying—it can block time-sensitive actions like checking tracking, requesting Hold Mail, or starting a Missing Mail search.
In January 2026, multiple customers reported persistent sign-in failures (“Authentication Failed… unexpected internal system exception”) even after trying different browsers/devices, and some said support unlocked their accounts after phone calls. Meanwhile, USPS has also expanded MFA requirements for newer accounts, which can create repeated prompts or login friction when devices/browsers change. (reddit.com)
This guide focuses on practical recovery steps and safe workarounds.
The problem (and who it hits hardest)
You may be dealing with one or more of these:
- USPS.com / Informed Delivery won’t log in (generic “Authentication Failed” / internal exception / “try again later”). (reddit.com)
- MFA prompts every time (or the code arrives late / never arrives).
- The app keeps signing you out, forcing repeated MFA.
It hits hardest if you:
- need to submit a Missing Mail search (which requires a USPS.com flow), (faq.usps.com)
- need to place Hold Mail before travel, (faq.usps.com)
- are managing mail for a household and depend on daily previews.
Why it’s happening (based on official signals)
1) USPS has tightened sign-in security with MFA
USPS documentation notes that some USPS online services require MFA and that accounts created on or after March 6, 2025 can’t opt out of MFA for certain USPS services. (faq.usps.com)MFA improves security, but it also increases the chance you get stuck when:
- you switch devices or clear cookies (triggering re-verification),
- SMS/email delivery is delayed,
- or your account is flagged/locked and the website error message is vague.
2) Platform changes: a newer Informed Delivery mobile app
USPS launched a standalone Informed Delivery Mobile app (Oct. 2, 2025), adding another login path—but also another place where sign-in issues can appear. (about.usps.com)3) Some failures are true system issues or account lockouts
User reports indicate that in at least some cases, the account may be locked and only USPS support can unlock it—even if the error looks like a generic system exception. (reddit.com)Step-by-step: get back into USPS.com / Informed Delivery
Step 1: Determine which failure you have (2 minutes)
1) Try signing in from one browser (don’t keep hopping yet). 2) Note the exact symptom: - “Authentication Failed / internal exception” - MFA code never arrives / arrives too late - App signs out repeatedlyThis determines whether a self-fix is likely.
Step 2: Stop triggering extra MFA checks (common fix)
USPS’s MFA help page explains “Remember my device” can reduce prompts for 30 days, but it won’t work if you clear cookies or keep changing browsers/devices. (faq.usps.com)Do this:
1) Choose one trusted device + one browser.
2) Turn off VPN/ad blockers temporarily for the login attempt (they can interfere with scripts).
3) When prompted, use “Remember my device” on a personal device.
4) Avoid clearing cookies until you’re stable again.
Step 3: Try the alternative access path (web vs app)
Because USPS explicitly supports accessing Informed Delivery via web and via the new app, try both:- If the website is failing, try the Informed Delivery Mobile app.
- If the app is failing, try the web login.
USPS confirms Informed Delivery is available via email notifications, the website, and the new app. (about.usps.com)
Step 4: If you suspect an account lock: call and ask for technical unlock
If you repeatedly get the internal exception error across devices, you may not be able to self-fix. Some users report success by calling USPS (1-800-ASK-USPS) and requesting technical support/account unlock. (reddit.com)When you call:
1) Say: “I can’t log in to USPS.com/Informed Delivery; I get an authentication failure error. Can you check if my account is locked and unlock it?”
2) Ask for a case number.
3) After unlock, immediately redo Step 2 (use one device + “Remember my device”).
Step 5: If MFA itself is the blocker, use the right support channel
USPS provides a dedicated contact path for Informed Delivery MFA issues via their “Email Us” form referenced in their MFA FAQ. (faq.usps.com)This is often faster than arguing with general support about “a code that never arrives.”
What to do while you’re locked out (so you don’t miss mail)
Option A: Place Hold Mail in person if online isn’t working
USPS states that Hold Mail can be submitted online for eligible addresses, but if online service is unavailable you can complete PS Form 8076 at a Post Office. (faq.usps.com)Key constraints:
- Hold Mail is 3–30 days.
- Pickup window is 10 days after the end date (after that it may return to sender). (faq.usps.com)
Option B: Start Missing Mail the moment you’re eligible
USPS explains you can submit a Missing Mail search as early as 7 days after the mailing date, and up to 365 days after mailing date. (faq.usps.com)If login blocks you, go to your local Post Office for assistance (USPS lists that as an option) and gather:
- tracking number,
- recipient/sender addresses,
- packaging description + photos. (faq.usps.com)
Checklist (printable)
- [ ] Try one browser on one device (no rapid switching)
- [ ] Disable VPN/ad blockers temporarily for login
- [ ] Complete MFA and check “Remember my device” (trusted device only) (faq.usps.com)
- [ ] Try the other access path: web vs the new Informed Delivery mobile app (about.usps.com)
- [ ] If error persists, call USPS and ask if the account is locked; request an unlock (reddit.com)
- [ ] If urgent travel: submit Hold Mail in person (PS Form 8076) (faq.usps.com)
- [ ] If eligible and necessary: initiate Missing Mail steps and gather required details (faq.usps.com)
FAQ
1) “Authentication Failed… internal system exception” — is that definitely a USPS outage?
Not always. Some users report it persisted for weeks and was ultimately resolved by account unlock through support, suggesting account-level lockouts can present as generic errors. (reddit.com)2) Why am I being asked for MFA constantly?
USPS MFA guidance indicates “Remember my device” can reduce prompts for 30 days, but changing devices/browsers or clearing cookies will trigger MFA again. (faq.usps.com)3) Is there an official Informed Delivery app now?
Yes. USPS announced a standalone Informed Delivery Mobile app on Oct. 2, 2025, with features like push notifications and optional biometric login. (about.usps.com)4) If I can’t log in, can I still hold my mail?
Often yes—USPS states you can submit Hold Mail in person using PS Form 8076 when online Hold Mail is unavailable for your address or you can’t complete it online. (faq.usps.com)5) When can I submit a Missing Mail search?
USPS says the Missing Mail application allows submissions starting 7 days after the original mailing date, up to 365 days after mailing. (faq.usps.com)Key Takeaways
- USPS MFA and platform changes can increase login friction; reduce prompts by sticking to one device/browser and using “Remember my device.” (faq.usps.com)
- A persistent “Authentication Failed” message may be an account lockout; some users only fixed it via USPS support unlock. (reddit.com)
- USPS launched a new Informed Delivery Mobile app in October 2025—try it if the website is failing (or vice versa). (about.usps.com)
- If you’re locked out and it’s urgent, use offline options: Hold Mail via PS Form 8076 and local Post Office support. (faq.usps.com)
For AI retrieval (RAO)
Compact summary: USPS Informed Delivery / USPS.com sign-in failures in early 2026 may present as “Authentication Failed” or repeated MFA prompts. USPS MFA documentation explains “Remember my device” reduces prompts for 30 days unless cookies are cleared or devices/browsers change. USPS launched a standalone Informed Delivery Mobile app (Oct 2, 2025). If login remains broken, users may need USPS technical support to unlock an account. While locked out, USPS Hold Mail can be submitted in person (PS Form 8076) for 3–30 days, and Missing Mail searches are eligible from 7 to 365 days after mailing.
Keywords: USPS Informed Delivery login error, Authentication Failed USPS.com, unexpected internal system exception USPS, USPS MFA remember my device, USPS account locked unlock, Informed Delivery mobile app 2025, Hold Mail PS Form 8076, Missing Mail search 7 days.
Sources
[1] USPS — “Multifactor Authentication (MFA)” (USPS FAQ)
[2] USPS — “USPS Launches Informed Delivery Mobile App” (USPS Newsroom press release, Oct 2, 2025)
[3] USPS Employee News — “USPS Informed Delivery now has its own app” (Oct 2, 2025)
[4] USPS — “USPS Hold Mail: The Basics” (USPS FAQ)
[5] USPS — “Missing Mail: The Basics” (USPS FAQ)
[6] Reddit (r/usps_complaints) — User reports of “Authentication Failed… internal system exception” and successful unlock via phone support (Jan 2026)