Hi, This is Bryll
Thank you for writing us here in Microsoft Community.
I agree that you have successfully added other email accounts in Outlook desktop application before without any problem however email hosts or email service providers have different level of security on their services which is why other email accounts can be added easily unlike with Gmail.
Gmail email addresses have their own security measures in place which can help protect the account from unauthorized access and malicious emails. To know more about Gmail accounts, you may talk to Google support technicians.
For adding a newly created Gmail.com email address in Outlook desktop application, here are some things that you may need to consider:
1. Make sure that you have enabled IMAP access in your Gmail account. You can do this by going to your Gmail settings, clicking on the "Forwarding and POP/IMAP" tab, and then selecting "Enable IMAP".
2. Try adding your Gmail account to Outlook using the manual setup option.
In Outlook application, go to File > Add Account > Manual setup or additional server types > choose IMAP. Then, enter your Gmail account information and the following server settings:
Incoming mail server: imap.gmail.com
Outgoing mail server: smtp.gmail.com
Username: your full Gmail email address
Password: your Gmail password
Once done, go to More settings > Outgoing Server tab, click My outgoing server SMTP requires authentication
Go to Advanced then use the following Server port numbers:
Incoming server IMAP 993
Use the following type of encrypted connection SSL
Outgoing server SMTP 465
Use the following type of encrypted connection SSL
3. If the manual setup option doesn't work, try clearing your Outlook cache.
To do this, go to File > Options > Advanced > Outlook Data File Settings > Compact Now. Then, restart Outlook and try adding your Gmail account again.
4. Create new Outlook profile:
- Open the Control Panel and click Mail.
- In the Mail Settings dialog box, click Show Profiles.
- Click Add to create a new profile and enter a name for it.
- Follow the instructions to add your email account to the new profile.
- Once done, click Finish and then select the new profile as the default profile.
- Restart Outlook and see if you can send emails now.
If above strategies do not work, have a look on this link and follow other instructions: Fix problems connecting your Google account to the Microsoft Cloud - Microsoft Support
Should problem remain, please send us some screenshots of the issue so we can recommend other strategies.
Kindly send us a reply if there is any misunderstanding or clarifications to our description.
Yours truly,
Bryll
Microsoft Moderator