# Critical Auth Error: "Malformed Link" blocking all user logins (Server-side redirect bug)

**URL:** <https://community.glideapps.com/t/critical-auth-error-malformed-link-blocking-all-user-logins-server-side-redirect-bug/87513>\
**Category:** Ask for Help\
**Created:** [July 28, 2026, 5:44pm UTC](https://community.glideapps.com/t/critical-auth-error-malformed-link-blocking-all-user-logins-server-side-redirect-bug/87513 "2026-07-28T17:44:37Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Kristers\_Vaivods](https://sea2.discourse-cdn.com/flex002/user_avatar/community.glideapps.com/kristers_vaivods/32/90735_2.png) [@Kristers\_Vaivods](https://community.glideapps.com/u/Kristers_Vaivods)\
**Post date:** [July 28, 2026, 5:44pm UTC](https://community.glideapps.com/t/critical-auth-error-malformed-link-blocking-all-user-logins-server-side-redirect-bug/87513/1 "2026-07-28T17:44:37Z")

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Hi everyone,

I’m experiencing a critical authentication issue on my Glide app. Whenever a user tries to sign in (via Google or email), the authorization fails immediately after approval with the following error:

> _“Sign-in failed: This sign-in link is malformed. Open the app again.”_

**Here is what I’ve already checked:**

- It happens across **all devices, networks, and browsers** (incognito mode, Safari, Chrome, Samsung Internet, etc.).

- It affects **all users** , completely locking everyone out of the paid functionality.

- This is clearly a server-side authentication/redirect URL issue on Glide’s end for this specific project.

Support and the AI bot keep suggesting clearing cache or checking extensions, but this is happening globally for the app.

Has anyone else experienced this recently, or can a Glide team member please escalate this to engineering? My app is currently completely unusable.

Thanks for any help or insights!

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<div class="post-metadata">

**Author:** ![Darren\_Murphy](https://sea2.discourse-cdn.com/flex002/user_avatar/community.glideapps.com/darren_murphy/32/47326_2.png) [@Darren\_Murphy](https://community.glideapps.com/u/Darren_Murphy)\
**Post date:** [July 28, 2026, 11:32pm UTC](https://community.glideapps.com/t/critical-auth-error-malformed-link-blocking-all-user-logins-server-side-redirect-bug/87513/2 "2026-07-28T23:32:57Z")

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I believe a fix for this issue was deployed a few hours ago.

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<div class="post-metadata">

**Author:** ![Kristers\_Vaivods](https://sea2.discourse-cdn.com/flex002/user_avatar/community.glideapps.com/kristers_vaivods/32/90735_2.png) [@Kristers\_Vaivods](https://community.glideapps.com/u/Kristers_Vaivods)\
**Post date:** [July 29, 2026, 4:13pm UTC](https://community.glideapps.com/t/critical-auth-error-malformed-link-blocking-all-user-logins-server-side-redirect-bug/87513/3 "2026-07-29T16:13:32Z")

</div>

Sadly did not help me.

Diagnostic Data:

GlideOS sign-in handoff diagnostic  
time: 2026-07-29T16:02:58.779Z  
request: POST /api/app-login/p0371b2a2-gramatas/handoff  
failure: http  
status: 400  
handoff-code: invalid\_return\_to  
content-type: application/json  
body-is-json: true  
cf-ray: a22d59d54b7d440a-VNO  
server: cloudflare  
user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:153.0) Gecko/20100101 Firefox/153.0

```auto
Problem Description:
* The app successfully loads and opens fine via the custom domain (`www.kodoligi.lv`).

* However, authentication and sign-in fail completely with a `400` status code and a `invalid_return_to` handoff error.

* The domain was recently changed from its Punycode version (`xn--kodolgi-9za.lv`) to the standard text format (`www.kodoligi.lv`), but this did not resolve the issue.

* DNS CNAME records and domain re-linking have been verified and re-configured multiple times, but the authorization flow still rejects the return URL.
```