[BUG] Sign in with Google button fires but OAuth callback handler never registers — All /auth paths return 404 — Windows 11

Google Antigravity
1

Environment

Field Value
OS Windows 11
Antigravity Version 1.20.4
Install Path (original) C:\Users\budok\AppData\Local\Programs\Antigravity\
Install Path (reinstall attempt) C:\Program Files\Antigravity\
Install Method (original) winget (Google.Antigravity)
Install Method (reinstall) Direct download from antigravity.google/download, run as Administrator
Default Browser Google Chrome (ChromeHTML)
Antivirus McAfee Antivirus + Advanced Firewall
HOME variable C:\Users\budok (confirmed set)

Summary

After a clean winget installation of Antigravity 1.20.4 on Windows 11, the “Sign in with Google” button on the login screen either produces no response or a brief cursor animation with no browser window opening. The BrowserOnboardingClientServer starts successfully on a localhost port, but all OAuth callback paths (/auth, /oauth-callback, /signin) return HTTP 404 Not Found. Google sign-in never completes and Antigravity remains stuck on the login screen indefinitely.

Symptoms

  1. Antigravity window opens normally and displays the “Sign in with Google” button

  2. Clicking the button either:

    • Produces a brief cursor animation with no browser window opening, OR

    • Has no visible response whatsoever (no cursor change, no animation)

  3. Terminal output shows BrowserOnboardingClientServer starts successfully on localhost

  4. Manually navigating Chrome to http://localhost``:<port>/auth, /oauth-callback, and /signin all return Not Found

  5. The “Browser Control” welcome page loads successfully at http://localhost:<port>/ confirming the server is alive

Terminal Output (Representative)

text

[main 2026-03-12T06:34:10.047Z] [BrowserOnboardingClientMainService] Starting browser onboarding server
[main 2026-03-12T06:34:10.168Z] [BrowserOnboardingClientServer] Browser onboarding server started on http://localhost:55474
[main 2026-03-12T06:34:11.036Z] update#setState idle
[30588:0311/232945.545:ERROR:net\socket\ssl_client_socket_impl.cc:916] handshake failed; returned -1, SSL error code 1, net_error -202
[main 2026-03-12T06:30:02.767Z] update#setState checking for updates
[main 2026-03-12T06:30:02.824Z] update#setState downloading
[main 2026-03-12T06:30:02.826Z] update#setState downloaded
[main 2026-03-12T06:30:02.827Z] update#setState updating
[main 2026-03-12T06:30:54.353Z] update#setState ready

Troubleshooting Steps Attempted (in order)

1. Verified winget installation and PATH

  • Confirmed Antigravity.exe installed via winget install -e --id Google.Antigravity

  • Verified PATH via Get-Command Antigravity.exe

  • Manually added install directory to user PATH via [Environment]::SetEnvironmentVariable

2. Cache clearing (selective)

Deleted the following directories and files:

  • %AppData%\Antigravity\Cache

  • %AppData%\Antigravity\GPUCache

  • %AppData%\Antigravity\CachedData

  • %AppData%\Antigravity\Code Cache

  • %AppData%\Antigravity\User\globalStorage\google.antigravity

  • %AppData%\Antigravity\User\globalStorage\state.vscdb

  • %AppData%\Antigravity\User\globalStorage\state.vscdb.backup

  • %AppData%\opencode\antigravity-accounts.json

3. Cache clearing (nuclear)

Renamed entire %AppData%\Antigravity and %LocalAppData%\Antigravity directories to .BAK backups. Relaunched from clean state. Issue persisted.

4. Verified HOME environment variable

Confirmed HOME was already correctly set to C:\Users\budok at the User level via:

powershell

[Environment]::GetEnvironmentVariable("HOME", "User")
# Output: C:\Users\budok

5. Protocol handler verification

Checked HKCR:\antigravity registry key and manually re-registered the antigravity:// protocol handler pointing to Antigravity.exe "%1".

6. Killed all related processes before launch

Terminated Antigravity, language_server_windows, Code, node, and electron processes via PowerShell before each launch attempt.

7. Launched with --ignore-certificate-errors

powershell

Start-Process "C:\Users\budok\AppData\Local\Programs\Antigravity\Antigravity.exe" `
-ArgumentList "--ignore-certificate-errors"

This suppressed the ssl_client_socket_impl.cc net_error -202 SSL error from terminal output. Sign-in button behavior unchanged.

8. Launched with --disable-gpu and --disable-gpu-compositing

powershell

Start-Process "...\Antigravity.exe" `
-ArgumentList "--disable-gpu", "--disable-gpu-compositing", "--ignore-certificate-errors"

No change in sign-in button behavior.

9. McAfee firewall configuration

  • Added Antigravity.exe as a Trusted Application in McAfee Advanced Firewall

  • Added chrome.exe as fully allowed for inbound/outbound

  • Added a custom TCP loopback rule allowing 127.0.0.1 on all ports for Antigravity.exe

  • Result: Worsened behavior — button became completely unresponsive with no cursor animation at all

  • Reverted all McAfee rules to original state; button returned to brief animation with no browser launch

10. Verified onboarding server port is active

powershell

netstat -ano | findstr "55474"
# Output: TCP 127.0.0.1:55474 0.0.0.0:0 LISTENING 3980

Confirmed server is listening. Root page http://localhost:55474/ loads “Welcome to Antigravity Browser Control” successfully.

11. Manual OAuth path testing

Manually opened the following paths in Chrome while Antigravity was running:

  • http://localhost:<port>/oauth-callback → 404 Not Found

  • http://localhost:<port>/auth → 404 Not Found

  • http://localhost:<port>/signin → 404 Not Found

Confirms the OAuth callback handler is never registered on the onboarding server.

12. Uninstalled via winget and cleared residual data

  • Terminated all related processes (Antigravity, language_server_windows, node, electron)

  • Ran winget uninstall --id Google.Antigravity

  • Deleted all residual folders:

    • %AppData%\Antigravity

    • %LocalAppData%\Antigravity

    • %LocalAppData%\Programs\Antigravity

13. Attempted winget machine-scoped reinstall

  • Attempted winget install --id Google.Antigravity --scope machine

  • Failed with: No applicable installer found; see logs for more details

  • Root cause: Google’s winget package manifest only ships a user-scoped installer; --scope machine is unsupported for this package

14. Reinstalled via direct installer download as Administrator

  • Downloaded installer directly from https://antigravity.google/download

  • Ran installer executable as Administrator via:

    powershell

    Start-Process $installer -Verb RunAs -Wait

  • Changed install location during wizard to C:\Program Files\Antigravity\

  • Relaunched from C:\Program Files\Antigravity\Antigravity.exe with flags --disable-gpu --ignore-certificate-errors

  • All OAuth callback paths still returned 404 Not Found

  • Issue fully persisted after machine-scoped reinstall

Hypothesis

Based on the observed behavior, the BrowserOnboardingClientServer starts successfully but the OAuth route handler (/auth or equivalent) is never registered during server initialization. This appears consistent with the Failed to set path bug reported in [winget-pkgs issue #333322] and [Antigravity-Manager issue #1916], where an internal path resolution error in main.js silently prevents the OAuth callback route from mounting. The SSL handshake error (net_error -202) may be a contributing factor if the route registration depends on a successful upstream TLS connection at startup.

Expected Behavior

Clicking “Sign in with Google” should open a Chrome window redirecting to https://accounts.google.com, complete OAuth, and return an auth token to the local callback server to finish setup.

Actual Behavior

No browser window opens. The local onboarding server runs but all OAuth-related paths return 404 Not Found. Setup never completes.

Requested Actions

  1. Confirm whether net_error -202 at startup is blocking OAuth route registration

  2. Provide a supported method to authenticate via API key or GCP service account as an alternative to OAuth (for Windows users blocked by this issue)

  3. Publish a machine-scoped (--scope machine) winget installer to support C:\Program Files\ installations

1 Like
2

Im getting the same issue!