Why Your Gmail Connection Fails and How to Fix It

Common reasons Gmail connection fails

When Connect Gmail or adding a Gmail account fails in EmaReach, it is usually due to credentials, security settings, or plan limits. Below are the most common causes and how to fix them.

1. Invalid credentials (App Password)

Symptom: "Invalid credentials" or "Authentication failed".

Fix:

• You must use an App Password, not your normal Gmail password. In Google Account → Security → 2-Step Verification → App passwords, generate a new App Password for Mail / Other (EmaReach) and paste it into EmaReach (Settings → Integrations → Gmail → Connect via App Password).
• Ensure 2-Step Verification is turned on; without it, App Passwords are not available.

2. Google OAuth credentials not set

Symptom: "Google OAuth credentials not set" or you cannot use "Connect with Google".

Fix: An admin must add Google Client ID and Client Secret in EmaReach (Settings → Integrations → Gmail). See our blog "How to Set Up Google Client ID and Secret for Gmail" for the full steps. After they are saved, try Connect with Google again.

3. Redirect URI mismatch (OAuth)

Symptom: After signing in with Google, you see "Redirect URI mismatch" or "Error 400".

Fix: In Google Cloud Console, the Authorized redirect URI for your OAuth client must match exactly the URI shown in EmaReach when you add credentials (Settings → Integrations → Gmail). Copy the URI from EmaReach and paste it into Google Cloud; do not type it by hand. Then try connecting again.

4. Plan limit reached

Symptom: "You have reached the Gmail limit for your plan" or similar.

Fix: Your plan allows only a certain number of Gmail accounts. Disconnect an unused Gmail in Settings → Integrations → Gmail, or upgrade your plan to add more.

5. App not verified (OAuth)

Symptom: Google shows "This app isn’t verified" when you try to sign in.

Fix: For testing, you can choose Advanced → Go to EmaReach (unsafe) to continue. For production, consider submitting your app for Google verification so the warning goes away.

Summary

Check: App Password (not normal password) and 2-Step Verification; OAuth Client ID/Secret and redirect URI; plan Gmail limit; and app verification if using OAuth.