%PDF-1.4 %âãÏÓ 1 0 obj << /Type /Catalog /Pages 2 0 R >> endobj 2 0 obj << /Type /Pages /Count 2 /Kids [5 0 R 7 0 R] >> endobj 3 0 obj << /Type /Font /Subtype /Type1 /BaseFont /Helvetica >> endobj 4 0 obj << /Type /Font /Subtype /Type1 /BaseFont /Helvetica-Bold >> endobj 5 0 obj << /Type /Page /Parent 2 0 R /MediaBox [0 0 595.28 841.89] /Resources << /Font << /F1 3 0 R /F2 4 0 R >> >> /Contents 6 0 R >> endobj 6 0 obj << /Length 4972 >> stream BT /F2 22 Tf 0.06 0.08 0.12 rg 1 0 0 1 46 789.89 Tm (How to Fix UpNote Login Error 400) Tj ET BT /F2 22 Tf 0.06 0.08 0.12 rg 1 0 0 1 46 762.89 Tm (\(createACToken\)) Tj ET BT /F2 11 Tf 0.72 0.14 0.18 rg 1 0 0 1 46 725.89 Tm (TechRounder PDF Edition) Tj ET BT /F1 9.5 Tf 0.36 0.39 0.46 rg 1 0 0 1 46 709.89 Tm (Live article: https://www.techrounder.com/how-to/how-to-fix-upnote-login-error-400-createactoken/) Tj ET q 0.82 0.85 0.9 RG 1 w 46 691.39 m 549.28 691.39 l S Q BT /F1 10 Tf 0.24 0.27 0.32 rg 1 0 0 1 46 679.39 Tm (By Vipin PG | Published July 16, 2026 | Updated July 16, 2026 | Format: Guide | 3 min read) Tj ET BT /F2 13 Tf 0.72 0.14 0.18 rg 1 0 0 1 46 656.39 Tm (Quick answer) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 636.39 Tm (If UpNote shows "Request failed with status code 400: POST) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 621.39 Tm (https://us-central1-get-senna.cloudfunctions.net/createACToken" when signing in, it means the app's) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 606.39 Tm (Firebase App Check verification step failed. As confirmed by UpNote's own support team, this specific) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 591.39 Tm (error is currently caused by high server load on their end, not a problem with your device, network,) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 576.39 Tm (or account. The fix is simple: wait and try signing in again after a few hours. Your notes stay safe) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 561.39 Tm (locally and will sync automatically once sign-in succeeds.) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 536.39 Tm (I ran into this while trying to sign in to UpNote on my Mac. The app just wouldn't log in, and instead) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 521.39 Tm (threw this cryptic error:) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 499.39 Tm ("Request failed with status code 400: POST) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 484.39 Tm (https://us-central1-get-senna.cloudfunctions.net/createACToken") Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 462.39 Tm (No explanation, no obvious next step - just a broken sign-in and a URL that looked like something meant) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 447.39 Tm (for developers, not regular users. Since I couldn't find a clear answer anywhere, I went through the) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 432.39 Tm (troubleshooting myself, step by step, until I found the actual cause. Here's everything I tried, in order,) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 417.39 Tm (and what finally explained it.) Tj ET BT /F2 15 Tf 0.08 0.1 0.14 rg 1 0 0 1 46 389.39 Tm (Step 1: Update UpNote to the Latest Version) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 365.39 Tm (The first thing I checked was whether I was running an outdated version, since a similar-looking error) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 350.39 Tm (\("firebase-app-check-token-is-invalid"\) is known to get fixed by updating. I went to Settings > Help >) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 335.39 Tm (Check for updates, and confirmed I was already on the latest version, 9.19.1. That ruled out the most) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 320.39 Tm (common fix right away.) Tj ET BT /F2 15 Tf 0.08 0.1 0.14 rg 1 0 0 1 46 292.39 Tm (Step 2: Clear UpNote's Local App Data) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 268.39 Tm (Next, I figured a corrupted or stuck local cache might be causing the sign-in token to fail. I fully quit) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 253.39 Tm (UpNote and deleted its local data folder:) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 231.39 Tm (`~/Library/Containers/com.getupnote.desktop/Data/Library/Application Support/UpNote/`) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 209.39 Tm (I relaunched the app and tried signing in fresh. Same error, no change. This ruled out a local cache) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 194.39 Tm (issue.) Tj ET BT /F2 15 Tf 0.08 0.1 0.14 rg 1 0 0 1 46 166.39 Tm (Step 3: Check the System Clock) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 142.39 Tm (Firebase App Check tokens are time-sensitive, so even a small clock drift can cause a login to be) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 127.39 Tm (rejected. I checked System Settings > General > Date & Time and confirmed "Set automatically" was) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 112.39 Tm (already enabled. Not the cause either, but worth ruling out since it's a two-second check.) Tj ET BT /F2 15 Tf 0.08 0.1 0.14 rg 1 0 0 1 46 84.39 Tm (Step 4: Test the Network - Disable Pi-hole and Change DNS) Tj ET q 0.86 0.88 0.92 RG 1 w 46 42 m 549.28 42 l S Q BT /F1 8.4 Tf 0.42 0.45 0.5 rg 1 0 0 1 46 30 Tm (TechRounder | Page 1 of 2) Tj ET BT /F1 7.2 Tf 0.42 0.45 0.5 rg 1 0 0 1 46 19 Tm (https://www.techrounder.com/pdf/blog/how-to-fix-upnote-login-error-400-createactoken.pdf) Tj ET endstream endobj 7 0 obj << /Type /Page /Parent 2 0 R /MediaBox [0 0 595.28 841.89] /Resources << /Font << /F1 3 0 R /F2 4 0 R >> >> /Contents 8 0 R >> endobj 8 0 obj << /Length 4338 >> stream BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 789.89 Tm (Since I run Pi-hole with DNS-over-HTTPS at home, my next suspicion was that a blocklist was silently) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 774.89 Tm (blocking Google/Firebase or Apple's App Attest domains. I disabled Pi-hole and also changed my DNS) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 759.89 Tm (settings directly to rule out any filtering. I tried signing in again. Still the exact same 400 error. This) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 744.89 Tm (ruled out DNS and local network blocking entirely.) Tj ET BT /F2 15 Tf 0.08 0.1 0.14 rg 1 0 0 1 46 716.89 Tm (Step 5: Check Console.app for the Real Error) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 692.89 Tm (With hardware and network ruled out, I opened Console.app to see if there was a more specific error) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 677.89 Tm (hiding behind the generic 400 message. This is a good habit for any app-level login failure on Mac - it) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 662.89 Tm (often reveals whether the problem is local \(like a failed device attestation\) or purely server-side.) Tj ET BT /F2 15 Tf 0.08 0.1 0.14 rg 1 0 0 1 46 634.89 Tm (Step 6: The Real Cause - Confirmed by UpNote Support) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 610.89 Tm (After ruling out the app version, local cache, system clock, and the entire network path, I checked) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 595.89 Tm (UpNote's own help documentation directly for this exact error message. That's where I found the real) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 580.89 Tm (answer: UpNote's support page confirms this specific 400 error on the createACToken request is) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 565.89 Tm (caused by high load on their servers, and they were actively working on resolving it.) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 543.89 Tm (In other words - nothing on my end was ever going to fix it. It wasn't my Mac, my network, or my) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 528.89 Tm (DNS. It was UpNote's backend struggling with request volume.) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 506.89 Tm (Good to know:) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 484.89 Tm (While you're signed out, UpNote still works completely fine offline. Any notes you write will be saved) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 469.89 Tm (locally on your device and will automatically sync to the server the moment you're able to sign in again) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 454.89 Tm (- no data is lost in the meantime.) Tj ET BT /F2 15 Tf 0.08 0.1 0.14 rg 1 0 0 1 46 426.89 Tm (What to Do If You See This Error) Tj ET BT /F1 10.5 Tf 0.2 0.23 0.28 rg 1 0 0 1 46 402.89 Tm (1. Don't panic - it's very likely not your device or account.) Tj ET BT /F1 10.5 Tf 0.2 0.23 0.28 rg 1 0 0 1 46 386.09 Tm (2. Confirm you're on the latest UpNote version, just to rule that path out.) Tj ET BT /F1 10.5 Tf 0.2 0.23 0.28 rg 1 0 0 1 46 369.29 Tm (3. Wait a few hours and try signing in again - the issue tends to be intermittent, tied to load spikes rather) Tj ET BT /F1 10.5 Tf 0.2 0.23 0.28 rg 1 0 0 1 46 355.49 Tm (than a full outage.) Tj ET BT /F1 10.5 Tf 0.2 0.23 0.28 rg 1 0 0 1 46 338.69 Tm (4. Keep using UpNote normally while signed out; your notes will sync automatically once sign-in works) Tj ET BT /F1 10.5 Tf 0.2 0.23 0.28 rg 1 0 0 1 46 324.89 Tm (again.) Tj ET BT /F1 10.5 Tf 0.2 0.23 0.28 rg 1 0 0 1 46 308.09 Tm (5. If it persists for several days, reach out to UpNote support directly with the exact error text.) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 291.29 Tm (If you've been staring at this same error message wondering what's broken on your end - nothing is.) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 276.29 Tm (It's a temporary backend load issue on UpNote's side, and the only real fix right now is a bit of) Tj ET BT /F1 11 Tf 0.14 0.16 0.2 rg 1 0 0 1 46 261.29 Tm (patience.) Tj ET q 0.86 0.88 0.92 RG 1 w 46 42 m 549.28 42 l S Q BT /F1 8.4 Tf 0.42 0.45 0.5 rg 1 0 0 1 46 30 Tm (TechRounder | Page 2 of 2) Tj ET BT /F1 7.2 Tf 0.42 0.45 0.5 rg 1 0 0 1 46 19 Tm (https://www.techrounder.com/pdf/blog/how-to-fix-upnote-login-error-400-createactoken.pdf) Tj ET endstream endobj xref 0 9 0000000000 65535 f 0000000015 00000 n 0000000064 00000 n 0000000127 00000 n 0000000197 00000 n 0000000272 00000 n 0000000414 00000 n 0000005437 00000 n 0000005579 00000 n trailer << /Size 9 /Root 1 0 R >> startxref 9968 %%EOF