In order to fix the autocomplete issue please follow next steps:
1. Click New Email
2. Start typing the email address
When the autocomplete suggestion pops up, click the X in order to delete wrong address from cache
3. If its an address from the organization, start typing the recipient name, then click Ctrl+K and choose the right address.
Or click To... and find the recipient in the address book.
Else: Type the right email address manually
4. Click Send
5. If you didn’t receive a NDR regarding the sent email, the right email address was updated in cache
6. Else, click New Items in home tab
7. Click Contact
8. Fill contacts full name and the right email address
9. Click Save & Close
10.Open new email
11.Start typing the email address
Click the right address in autocomplete suggestions
12.Click Send
13.If you didn’t receive a NDR regarding the sent email, the right email address was updated in cache
*** Notice – next step will delete all autocomplete cache in outlook ***
14.Else, click File tab
15.Click Options
16.Click Mail
17.Click Clean Auto-complete list, then click OK
18.Click New Email
19.Type the right email address manually
20.Click send
21.If you didn’t receive a NDR regarding the sent email, the right email address was updated in cache
22.Else, please contact NDSN support team