A 5-minute walkthrough of why Outlook suddenly stops working with Gmail and how to fix it. The cause is Google retiring its Less Secure Apps feature in May 2022 (consumer Gmail) and January 2025 (Workspace), leaving Outlook unable to authenticate with the regular Gmail password. The fix is to generate a 16-character Gmail app password and paste it into Outlook in place of the old password.
Video Transcript
Hello and welcome to VideoShala. In this video we will solve the issue of Outlook stopping work with Gmail. It is true that Google has phased out its Less Secure Apps feature. That permission was what allowed Outlook to connect to Gmail using just the regular Gmail password. Google retired Less Secure Apps for personal Gmail in May 2022 and for Google Workspace in January 2025. So the fix is to use a 16-character Gmail app password instead.
Step one. Open myaccount.google.com/security in a browser. Confirm 2-Step Verification is on. If it is off, turn it on first because app passwords only work when 2-Step Verification is enabled.
Step two. Go to myaccount.google.com/apppasswords. Type a label like Outlook on Office Laptop. Click Create. Google shows a 16-character code in four groups of four characters. Copy the code without the spaces.
Step three. Open Outlook. Click File, Account Settings, then Account Settings again from the dropdown. Click your Gmail account in the list, then Change.
Step four. In the password field, delete your old Gmail password and paste the 16-character app password from step two. Confirm incoming server is imap.gmail.com on port 993 with SSL, and outgoing is smtp.gmail.com on port 465 with SSL. Click Next. Outlook tests the connection and shows two green checkmarks.
Step five. Close the dialog, fully close Outlook, then reopen it. Send yourself a test email from Gmail web to confirm receive works. Reply from Outlook to confirm send works. The fix is now permanent. The app password works until you revoke it or change your Gmail password. Thanks for watching and please subscribe.
Watch the full video above to see exactly where to click, then follow the written 6 steps underneath.
What you'll see in this video
- Confirming Gmail IMAP is on in Gmail settings
- Generating a fresh app password in Google Account
- Removing the broken Gmail account in Outlook
- Re-adding Gmail with the new 16-character app password
- Seeing the inbox sync correctly again
Why Outlook Stopped Working with Gmail
If Outlook was working fine with Gmail for years and then suddenly started failing with "authentication failed" or error 0x800CCC0E, the cause is almost always Google's phased deprecation of Less Secure Apps access. Less Secure Apps was the legacy mechanism that let any IMAP client (Outlook, Thunderbird, Apple Mail) connect to Gmail using just the regular email password. Google retired it for personal @gmail.com accounts on May 30, 2022 and for Google Workspace accounts in January 2025. The Outlook app, the Outlook config, and your Gmail password did not change; what changed is that the password you saved in Outlook stopped being a valid IMAP credential against Gmail's servers overnight.
The fix is to switch from your regular Gmail password to a 16-character app password generated from your Google Account. This page covers the 5-step procedure: enable 2-Step Verification (a prerequisite), generate the app password at myaccount.google.com/apppasswords, then paste it into Outlook's account settings in place of the old password. The fix is permanent. After this, Outlook will continue working with Gmail until you change your Gmail password (which invalidates all app passwords) or revoke the app password manually. For a deeper explanation of why Google made this change and the security model behind it, see our Gmail app password guide.
Outlook Error Messages Caused by This Issue
| Error or symptom | What it means |
|---|---|
| Error 0x800CCC0E | Outlook 2016/2019/2021 generic "the connection to the server has failed". Always check IMAP authentication first since this error has many root causes; in 2026 the Gmail Less Secure Apps deprecation accounts for the majority. |
| "Outlook needs a password" popup that keeps reappearing | Outlook is rejecting your saved password and asking for a new one, but no matter how many times you re-type the Gmail password, the popup returns. This is the canonical symptom of the Less Secure Apps issue. |
| "Authentication failed" in Account Settings test | When you click Test Account Settings in Outlook, both incoming and outgoing fail with red X marks and the same authentication error. The server hostname is correct, the port is correct, but Gmail rejects the password. |
| "Reconnect your account" yellow bar (new Outlook) | The new Outlook for Windows shows this banner when Gmail account auth has failed. Clicking it triggers an OAuth flow on supported versions; on older versions it just reprompts for password. |
| "Sync issues" folder appearing in Outlook | Outlook gives up after several auth failures and stops trying to sync. Mail accumulates as Sync issues errors. Once you fix auth, the sync issues clear themselves on the next successful connection. |
| Send works but receive does not (or vice versa) | The IMAP and SMTP credentials are configured separately in Outlook. If you fix the password in only one section, only that direction works. Always update both Incoming Server and Outgoing Server (SMTP) to use the same app password. |
| "Disconnected" status bar at bottom of Outlook | Outlook tried to authenticate, failed, and went into Disconnected mode to avoid hammering the server. Manual fix: File > Send/Receive groups > uncheck and recheck Online to force reconnect after fixing the password. |
5 Steps to Fix Outlook + Gmail
Follow along with the video above as you work through these steps. As shown in the clip, watch where the App passwords page sits in Google Account Security and how Outlook accepts the new code.
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Confirm 2-Step Verification is on. Open myaccount.google.com/security in a browser. Sign in to the Gmail account that is failing. Scroll to the How you sign in to Google section. Confirm 2-Step Verification shows On. If it is Off, click it and follow the prompts to enable it (Google sends an SMS code to your phone for verification). App passwords only work when 2-Step Verification is enabled; this is non-negotiable since 2022.
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Generate a 16-character app password. Go to myaccount.google.com/apppasswords directly (the link is only visible after 2-Step Verification is on). Type a label like Outlook on Office Laptop in the App name field. Click Create. Google shows a 16-character code displayed as four groups of four characters separated by spaces. Copy the code without the spaces. This page only shows the code once; if you close it without copying, you must generate a new one.
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Open Outlook Account Settings. Open Outlook. Click File in the top left, then Account Settings, then Account Settings again from the dropdown. The Account Settings dialog appears with a list of your configured email accounts. Click your Gmail account in the list, then click Change.
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Replace the old password with the app password. In the Change Account dialog, find the Password field. Delete whatever is there (your old Gmail password). Paste the 16-character app password from step 2 (without spaces). Confirm Incoming server is imap.gmail.com on port 993 with SSL/TLS, and Outgoing is smtp.gmail.com on port 465 with SSL or 587 with STARTTLS. Click Next. Outlook tests the connection and shows two green checkmarks if both incoming and outgoing succeed.
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Restart Outlook and verify mail flow. Close the Change Account dialog. Close Outlook fully (check Task Manager that outlook.exe is gone). Reopen Outlook. New mail starts arriving in the Gmail inbox folder. Send yourself a test email from Gmail web to confirm receive works. Reply to that test from Outlook to confirm send works. If both succeed, the fix is complete and the app password is now permanent (good until you revoke it or change your Gmail password).
Common Issues After Applying the Fix
| Issue | Cause and fix |
|---|---|
| "App passwords aren't available for your account" | Two reasons: 2-Step Verification is not enabled (turn it on at myaccount.google.com/security), or you are on Google Workspace and your administrator has disabled app passwords organisation-wide. For Workspace, ask the admin to enable app passwords for your unit, or use OAuth-based account setup in Outlook 365 instead. |
| App password works for receive but send still fails | Outlook keeps incoming and outgoing credentials in separate fields. The fix dialog you used may have only updated one of them. Open Account Settings > Change > More Settings > Outgoing Server tab > tick "My outgoing server (SMTP) requires authentication" and select "Use same settings as my incoming mail server". Save and retest. |
| Outlook prompts for password again after a few weeks | Three causes: (a) you changed your main Gmail password (this invalidates all app passwords), (b) you revoked the app password from myaccount.google.com/apppasswords, or (c) Google flagged unusual sign-in activity and reset all sessions. Generate a fresh app password and paste it into Outlook to recover. |
| Mail flow works but Outlook shows "Sync issues" folder with old errors | Cosmetic only; Sync issues clears itself on the next successful sync. To clear immediately, right-click the folder and select Delete All, then run Send/Receive once. |
| Outlook caches old password and ignores app password | Windows Credential Manager has a cached entry for the Gmail account. Open Control Panel > User Accounts > Credential Manager > Windows Credentials. Delete any entries with imap.gmail.com or smtp.gmail.com or your Gmail address. Restart Outlook; it will prompt for the password fresh, paste the app password. |
| Some messages stuck in Outbox after fix | Messages queued before the fix may need a manual retry. Click on the message in Outbox > right-click > Resume. Or move them out of Outbox to Drafts and re-send. |
| Two-factor SMS code prompt during account setup | Some Outlook versions trigger a 2FA challenge before accepting the app password. Complete the SMS code prompt; this is one-time per device. Outlook will not prompt again on the same machine. |
| "Invalid credentials" persists despite correct app password | Most likely you typed the app password with spaces (Google displays it as 4 groups of 4 with spaces). Spaces are display-only; remove them and paste the 16-character continuous string. If still failing, generate a fresh app password and try again. |
| Slow Outlook startup after fix | Outlook is rebuilding its IMAP folder cache against Gmail's labels. First startup after credential change can take 5-10 minutes for accounts with many labels. Subsequent startups return to normal speed. |
Why This Happened: Less Secure Apps Deprecation Timeline
| Date | Event |
|---|---|
| Pre-2014 | Gmail accepts plain IMAP/SMTP authentication with regular Gmail password. No 2FA, no app passwords. Outlook just works. |
| 2014 | Google introduces 2-Step Verification. Users with 2FA on must use app passwords for Outlook. Users without 2FA continue using regular password (called Less Secure Apps access). |
| October 2019 | Google announces upcoming deprecation of Less Secure Apps. The toggle remains on by default but Google starts showing security warnings. |
| February 2020 | Google removes the Less Secure Apps toggle for new G Suite accounts (Workspace predecessor). Existing accounts still have it. |
| May 30, 2022 | Google retires Less Secure Apps for all personal @gmail.com accounts. Mass Outlook breakage day. Millions of users see the password popup return and never go away. |
| September 2024 | Google announces final Workspace deprecation timeline. |
| January 2025 | Google retires Less Secure Apps for all Google Workspace accounts. Workspace users with Outlook see the same break that personal users saw in 2022. |
| 2026 onwards | App passwords or OAuth are the only ways for IMAP clients to connect to any Gmail account. The regular Gmail password is for the web sign-in only. |
App Password vs OAuth: Which Should You Use?
| Method | When to use |
|---|---|
| App password (this guide) | Works on every Outlook version from 2010 to 2026. Universal, simple, and reliable. The password is permanent until you revoke it. Only catch: if you change your Gmail password, all app passwords invalidate and you must regenerate. |
| OAuth 2.0 in Outlook 365 | Available in Outlook 365 (Microsoft 365 click-to-run, version 16.0.13929 and newer) and the new Outlook for Windows. When adding a Gmail account, Outlook opens a Google sign-in browser window. You sign in normally, approve access, no password is stored. Recovers from main password changes automatically. |
| OAuth 2.0 in Outlook 2019/2021 perpetual | Officially supported but inconsistent. Some perpetual builds offer Gmail OAuth flow, others fall back to password. If OAuth setup fails, drop back to app password method. |
| OAuth 2.0 in Outlook 2016 | Not supported. Outlook 2016 is too old to do OAuth against Gmail. App password is the only way. |
| Regular Gmail password (legacy) | No longer works in 2026 against any Gmail account. Even with 2-Step Verification off, Google has tightened restrictions and refuses regular passwords from third-party IMAP clients in nearly all cases. |
Should You Migrate Away from Outlook + Gmail?
If Outlook + Gmail keeps breaking and you are tired of re-pasting credentials, consider whether the combination is still right for you. A few alternatives:
| Alternative | Pros and cons |
|---|---|
| Stay with Outlook + Gmail using app password | Default choice. Free if you already pay for Outlook (M365 or perpetual). One-time setup, then years of reliable mail. App passwords are well-understood now. |
| Switch to Gmail web (gmail.com) | Gmail's web interface is the most feature-complete Gmail experience. Free, no installation, no IMAP issues. Better search, labels, filters than Outlook can offer against Gmail. The downside is no offline reading on a laptop without internet. |
| Switch to Thunderbird | Free open-source desktop client. Supports OAuth with Gmail out of the box. Less polished UI than Outlook but no licensing costs. Good for users who only want a desktop client and don't need Microsoft 365 features. |
| Migrate Gmail mailbox to Outlook.com or Office 365 | Move the actual mailbox to a Microsoft platform so it natively integrates with Outlook. Our Gmail to Office 365 migration guide covers the workflow. Best for users committed to the Microsoft ecosystem. |
| Use Gmail's Outlook for Web alternative | If you are on Microsoft 365, you can use Outlook on the web (outlook.live.com) which is browser-based and may be more reliable than the desktop client. Same features, different rendering engine. |
Security and Privacy Considerations
The app password is a 16-character secondary credential. Anyone who has the string can access your Gmail mailbox via IMAP indefinitely until you revoke the password from your Google Account app passwords page. Treat it like a physical key. Practical guardrails: (1) Generate one app password per device or client, with a clear label like "Outlook on Office Laptop", "Apple Mail on iPhone", "Thunderbird on Home Desktop". This way you can revoke a single device's access without breaking the others. (2) Never share the app password with anyone. Unlike your main Gmail password, the app password bypasses 2-Step Verification, so it has no second-factor protection. (3) When you sell or dispose of a device, revoke the app password for it before wiping the device. The app password could otherwise be recovered from the device's saved-credentials store. (4) Periodically review the active app passwords list at myaccount.google.com/apppasswords and delete any whose device you no longer have. Google does not auto-expire app passwords. (5) Changing your main Gmail password invalidates all app passwords; you must regenerate them. Some users use this as an annual "cleanup" practice.
đź’ˇ Pro tips
- Paste the app password without spaces. Google displays the 16-character code as four groups of four with spaces between (xxxx xxxx xxxx xxxx). The spaces are display-only; the actual password is the 16 continuous characters.
- Label app passwords clearly. Use device-specific labels like "Outlook on Office Laptop" instead of generic "Mail App". When something goes wrong, you can immediately tell which device's password to revoke.
- Check Windows Credential Manager if Outlook ignores the new password. Old cached entries can override your new app password silently.
- Try OAuth first on Outlook 365. Setup is simpler than app password and recovers from Gmail password changes automatically. If OAuth fails, fall back to app password.
- Update both Incoming and Outgoing settings. Outlook stores them separately. Update both to use the same app password to avoid send-but-not-receive (or vice versa) bugs.
- Generate a fresh app password if anything is unclear. Old app passwords can stack up over the years. When troubleshooting, the cleanest approach is: revoke all old app passwords, generate one new one, paste it everywhere needed.
- For shared computers, do not save the password in Outlook. Untick the Remember password checkbox during setup so the app password is not cached on disk.
- Document the recovery procedure for non-technical family members. The next time Outlook breaks, they have the steps to fix it without calling you.
- If 2-Step Verification feels like overkill, consider that without it your Gmail (and therefore Drive, Photos, Pay, contacts) is one phishing email away from being lost. The app password annoyance is genuinely worth the protection.
Frequently Asked Questions
Why did Outlook suddenly stop working with my Gmail account?
Google retired its Less Secure Apps access feature in two waves: May 30, 2022 for personal @gmail.com accounts and January 2025 for Google Workspace accounts. Outlook (and any other client using a regular password against Gmail IMAP/SMTP) was relying on Less Secure Apps to authenticate. When Google turned it off, the password Outlook had saved suddenly stopped working, even though nothing in Outlook or your Gmail password had changed. The fix is to switch from your regular Gmail password to a 16-character app password generated from your Google Account.
I do not see an App passwords option in my Google Account
App passwords are only available after 2-Step Verification is enabled on your Google Account. Go to myaccount.google.com/security and turn on 2-Step Verification first. The App passwords link then appears at myaccount.google.com/apppasswords. If you are on Google Workspace and the option still does not appear, your administrator has likely disabled app passwords for your organizational unit. Ask the admin to enable them, or use OAuth-based account setup in Outlook instead.
What error message does Outlook show when this happens?
The most common Outlook error is 0x800CCC0E: "The connection to the server has failed" or "Authentication failed". Some Outlook versions show a popup saying "Outlook needs a password" that keeps reappearing no matter how many times you re-enter the correct Gmail password. New Outlook for Windows shows "Sync issues" or a yellow warning bar saying "Reconnect your account". Older Outlook 2016/2019 may show a generic "Send/Receive error" in the status bar at the bottom.
Should I use OAuth instead of an app password?
If your Outlook version supports it, yes. Outlook 365 (Microsoft 365 subscription, click-to-run version 16.0.13929 and newer) and the new Outlook for Windows both support OAuth 2.0 with Gmail. OAuth opens a Google sign-in browser window, you approve access, and no password is stored anywhere. App passwords work fine but are more legacy. For older Outlook 2016/2019/2021 perpetual licenses, app passwords are typically the only path because OAuth support was added incrementally. Try OAuth first; fall back to app passwords if it fails.
Can I still use my regular Gmail password if 2-Step Verification is off?
Technically possible but discouraged and increasingly broken. Google has been narrowing the conditions under which a regular password works for IMAP. As of 2026, even with 2-Step Verification off, many accounts cannot use the regular Gmail password against Outlook because Google quietly disabled Less Secure Apps for them. The reliable path is: turn on 2-Step Verification, generate an app password, paste that into Outlook. This works in 100% of cases and is what Google recommends in their official documentation.
After fixing it, will Outlook break again?
App passwords are permanent until you revoke them or change your main Gmail password. Changing your main Gmail password automatically invalidates all app passwords on the account, so you must regenerate after any password change. If you ever notice Outlook prompting for the password again, the most likely cause is: (a) you changed your Gmail password, (b) you removed the app password from myaccount.google.com/apppasswords, or (c) Google flagged unusual sign-in activity and reset all sessions. Generate a fresh app password and paste it into Outlook to recover.