Fix: Your IMAP server wants to alert you ‘Invalid Credentials’

IMAP errors are particularly hard to tackle. This error is usually encountered when users try to access Gmail via IMAP on Outlook, Thunderbird, Apple Mail and other similar services. Most of the time, the error “invalid credentials” means that you’ve managed to enter the wrong username or password, or even incorrect server names/port numbers.

Most users will get this error as soon as they open Microsoft Outlook. After they close the error message, they are prompted to re-enter their email password. The problem is, in some cases, Outlook will repeat the same error message again and again even if the credentials are correct.

If you’re absolutely sure you have entered the correct credentials, the issue might originate from Google. In fact, the “Your IMAP server wants to alert you of the following: Invalid credentials” error is usually not caused by you or Outlook. It’s actually a Gmail defense mechanism for malicious things like automated scripts, robots and other account abusing practices.

Another reason for the appearance of this message is when users check their email too often, and Google mistakenly treats it as suspicious account activity. By default, Gmail guidelines advise users to avoid checking their emails in intervals shorter than every 10 minutes.

If you’re currently dealing with this issue, below you have a collection of methods that helped a lot of users get rid of the message.

Method 1: Unlocking and clearing the Captcha

When signing into a new device with your Gmail address, your account might require an additional step in order to function properly. If you didn’t already, unlocking the CAPTCHA and clearing it will most likely make the error message go away. Here’s what you need to do:

1. Acess this link and click the Continue button.
   
2. Enter your Google account username and password. Insert the CAPTCHA displayed and hit the Unlock button.
   
3. If you do it right, you should see an “Account access enabled” message.
   
4. Now return to Outlook, and re-insert your user credentials the next time the error message appears. It should stop bothering you after that.

Method 2: Allowing less secure apps

Another popular fix for this error message is to change your Gmail account settings to allow less secure apps to access your Gmail account. Don’t automatically assume Outlook is not secure, it’s just Google’s categorization. Anyways, here’s how to allow less secure apps to access your Gmail account:

1. Visit this link and insert your Google Account credentials.
2. Make sure the toggle next to “Access for less secure apps” is turned On.
   
3. Return to Outlook and insert re-insert your credentials. If all goes well, you shouldn’t be bothered by the same error message again.

Method 3: Enabling IMAP access in your Gmail Account

Even if IMAP enabled by default, there are cases where 3rd party services can interfere with this setting. If the two methods above have failed, it’s highly probable that IMAP is disabled in your Gmail account. Here’s how to enable it:

1. Access the web version of Gmail from this link and insert your user credentials.
2. Once you’re logged in, click the settings wheel in the top-right section of the screen. Then, click Settings from the drop-down menu.
   
3. Click the Forwarding and POP / IMAP tab to bring it forward. Then, scroll down and set IMAP Acess to Enable IMAP.
   
4. Close the web window, open Outlook again. The “Invalid credentials” error message should be removed.

Method 4: Configuring 2-Step Verification for Outlook

If you use 2-Step verification with Gmail, you’ll have to adapt it for Outlook. Some apps, including the default Windows Mail app and Outlook, do not support 2-Step Verification. Normally Google will send a verification code to your phone number, but with Outlook that’s not applicable. Instead, you’ll need to authorize the app by generating a specific app password for it. Here’s how:

1. Visit the App password page and sign-in with your Google account.
   
2. Google will send a confirmation prompt to your phone, hit Yes to confirm.
3. Select Mail in the first drop-down menu and Windows Computer in the second. Click the Generate button.
   
4. Copy the newly generated password from the yellow box.
   
5. Open Outlook and paste the generated password in the Password field and click OK.