Outlook Classic is Requiring a logon

Do not enter your Google password into a Microsoft-account sign-in form; add Gmail through classic Outlook and enter the password only in the Google sign-in window that Outlook opens.

If Gmail is configured in Outlook

The wording “Sign in to continue to Microsoft apps & services” can be part of Google’s authorization process, allowing Outlook to access Gmail.

1. Close the unexpected prompt.
2. In classic Outlook, select File > Add Account.
3. Enter your complete Gmail address and select Connect.
4. Outlook should open a Gmail Sign in window displaying the Gmail account being added.
5. Enter the Google password there and complete any Google two-step verification.
6. On the Google account permissions page, select Allow for Microsoft apps & services.
7. Wait for Outlook to confirm that the account was added, then select Done. This is Microsoft’s documented procedure for Outlook 2024 and classic Outlook. ^1^

If this prompt appeared while Outlook was synchronizing an existing Gmail account, complete the same Google authorization flow only if the window clearly identifies the correct Gmail account and requests permission for Microsoft apps and services.

If it is actually a Microsoft sign-in page

A Google password cannot be used to sign in to a Microsoft account. A Gmail address can be registered as the username for a Microsoft account, but that Microsoft account has its own password. ^2^

Therefore:

• If Outlook is requesting Office activation, enter the Microsoft-account credentials used to purchase or activate Office 2024—not the Google password.
• If the page asks for a Google password while presenting itself strictly as a Microsoft-account sign-in, cancel it.
• If the prompt came from an email link, attachment, advertisement, or unrelated browser page, do not enter any credentials. Credential requests from unexpected messages are a common phishing technique. ^3^

If the legitimate Google sign-in fails

First update Office:

1. Open Outlook.
2. Select File > Office Account.
3. Select Update Options > Update Now.
4. Restart Outlook and repeat File > Add Account.

If Outlook explicitly says that an app password is required, obtain one from Google and paste that generated password into Outlook instead of the normal Gmail password. App passwords apply only when the provider or account configuration requires them; they should not replace the normal browser-based Google authorization flow by default. ^4^

References

1. Classic Outlook
2. Link your Google account and Microsoft account
3. Phishing and suspicious behavior in Outlook | Microsoft Support
4. Classic Outlook