FIX: Error 78754 (Failure) when logging in to Gmail on Outlook

Madalina Dinita
by Madalina Dinita
Managing Editor
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Error 78754 (Failure)

The ‘error78754 failure’ is a web log-in error or IMAP glitch experienced by Google Mail subscribers on Outlook. The mail server forcibly shuts out clients while trying to gain access to their emails through the Microsoft Outlook platform.

The Gmail ‘error 78754 failure’ usually pops up when the password supplied by a user is not recognized, when a suspicious log-in is detected by Google or when a user is trying to access his account from a new device or location.

This error may also occur if an app-specific password is required for sign-in rather than the regular account password.

The error received while trying to log into your email account is presented in this format:

‘Our IMAP server wants to alert you to the following: Please log in via your web browser: ‘.

Before we proceed, it is imperative to get the reader acquainted with Internet Message Access Protocol (IMAP).

We’ve written extensively on Outlook and Gmail connection issues. Bookmark this page in case you need it later.

What is IMAP Server?

IMAP is a standard electronic mail protocol that stores messages on a mail server and then lets the end-user view, organizes and manipulate the emails as though they were originally stored on the user’s machine.

IMAP allows end-users to have multiple client (email platform) applications, organize mailbox contents into folders, and also know which messages have been read, sent, saved as a draft or flagged for urgency on the server.

Internet Message Access Protocol (IMAP) allows users to connect to the email server using different devices simultaneously and the messages are synchronized in real-time i.e. a user could set up his mail account on his Microsoft Outlook desktop client and his Outlook Android/iPhone app at the same time.

Read your emails on multiple platforms with these cross-platform email clients!

What is causing the ‘Error 78754 Failure’?

The Gmail ‘Error 78754 failure’ could be caused by any of the following reasons:

  • Google detects a suspicious login on your account.
  • The password you put in is not recognized or incorrect.
  • You are trying to sign in using a different device or from a new location.
  • You probably have two-step verification enabled on your account and an application-specific password is required before log-in can be possible.
  • Incorrect IMAP configuration or IMAP not enabled
  • Wrongly configured Microsoft Outlook
  • Outdated email client

How to resolve the ‘Error 78754: Failure’

To fix the web log-in error, follow these steps:

  1. Re-verify your Gmail log-in details
  2. Turn on IMAP and Allow less secure apps associated with your Gmail account
  3. Check your Microsoft Outlook and configure appropriately
  4. Verify if 2-step verification is enabled, then generate an app-specific password
  5. Update your Email Client (Outlook)

Step 1: Re-verify your Gmail log-in details

By simply verifying your log-in details to ensure that they are correct might save you a lot of stress. Hence, it should be your first point of call.

After confirming your details, try logging into your Outlook on your PC or mobile device and the error should be resolved.

Step 2: Turn on IMAP and Allow less secure apps associated with your Gmail account

To Enable IMAP on your Gmail account and also turn on Allow less secure apps, follow these steps:

  • Open your web browser and type in in the address bar
  • Login to Gmail with your details
  • Pan to the top right corner, click the Settings icon, and in the drop-down, select Settings.
  • Click on ‘’Forwarding and POP/IMAP.’’


  • Click the Enable IMAP button in the ‘’IMAP Access’’ and select Save Changes.


  • While still logged in, type in the URL bar.
  • Locate ‘’Allow less secure apps,’’ and click the turn on button to activate it.
  • Try logging into your Microsoft Outlook and the issue should be resolved.

 Step 3: Check your Microsoft Outlook and configure appropriately

The error 78754 failure may occur if an Outlook account is not correctly configured. To configure your Microsoft Outlook appropriately, see these steps:

  • Hold Winkey + Q or S and in the search bar, type in Outlook and press Enter.
  • In the next screen, enter your email address, check the ‘let me set up my account manually’ box and click Connect.



  • Select IMAP (for Windows 10 Operating System) or Google or POP or IMAP on other versions of Windows, then click
  • Ensure that IMAP or POP access is turned on before attempting to add your account to Outlook. Use this server information to appropriately configure your Outlook. Then click Next.

Here is the configuration you should use:

  • IMAP incoming mail server:
  • IMAP port:    993
  • IMAP SSL:    Yes
  • Encryption Method: SSL/TLS
  • SMTP outgoing mail server:
  • Requires SSL: Yes
  • Requires TLS: Yes (if available)
  • Requires Authentication: Yes
  • SMTP port for SSL:    465
  • SMTP port for TLS/STARTTLS:    587
  • POP incoming mail server:
  • POP port:    995
  • POP SSL:    Yes
  • You will be required to enter the password for your email account on the next screen. Slot in the correct password and click Connect.
  • Your Outlook should now be properly configured and the ‘error 78754 failure’ should be resolved.

Step 4: Verify if 2-step verification is enabled, then generate an app-specific password

If you have 2-step verification enabled on your Gmail account, then you must generate an App-specific password before you can sign in on any mail application (Outlook, MailExplorer etc.).

To generate an Application-specific password, follow these steps:

  • Sign-in to your Google mail account
  • Under the ‘’Sign-in and Security’’ section of your Account Setting Page, select ‘’Signing in to Google.’’
  • If 2-step verification is disabled, click on the arrow and follow the prompt.
  • After completing the 2-step verification activation procedure, you should have this: You can now go ahead to generate an app-specific password.
  • Click on the arrow for App passwords, verify your account using the 2-step verification and from the drop-down in the next screen, select Other (custom name- Outlook).

  • Type in the name of the APP and click Generate.
  • After clicking on Generate, your password will then come up.
  • Open Outlook, select and set up the appropriate server. Use the app-specific password already generated when required to enter your mail password. At this point, the ‘error 78754 failure’ should be fixed.

Step 5: Update your Email Client (Outlook)

Upgrading your email client (Microsoft Outlook) to the latest version might just be the simple fix you require. Visit the Microsoft Support page to choose a suitable version for your PC.

Switch email clients safely with these email migration tools from our fresh list!