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I understand how frustrating it is to spend time correcting emails only to have them revert to the wrong ones. This usually happens because Outlook "resolves" the name back to an outdated entry stored in its cache or address book when you hit Send.
To resolve this, please follow the steps below:
I. (Use "Check Names"): When you correct an email address in the meeting invite:
1. Do not just backspace and retype.
2. Instead, completely remove the wrong recipient block.
3. Type the correct email address manually.
4. Press Ctrl + K on your keyboard. This forces Outlook to validate the new address immediately.
5. Once the name is underlined/resolved correctly, you can send the invite.
II. To prevent this from happening in the long run, could you please clarify how these contact lists are currently stored? Are they from your Personal Contacts, the Global Address List (GAL), a Distribution List, or an Excel list you are copying from?
It is possible the "incorrect" email is stored permanently in one of those sources. Please try this quick test:
1. Create a new email/meeting.
2. Click the "To..." (or Required) button to open the Address Book.
3. Search for one of the people whose email keeps showing up incorrectly.
4. Double-click their name to view the properties and check if the email address displayed there is correct.
5. If it is incorrect there. You will need to update it in your Personal Contacts or, if it is a company contact (GAL), request your IT department to update it.
I hope this helps, at least partially. If you have any updates, questions, or if I misunderstood anything, please feel free to reach out anytime.
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