Until Microsoft adds a straightforward way to delete addresses from the suggested accounts list, you can try the steps below to remove addresses from the Suggested accounts list.
When I tested it, it removed Microsoft consumer and business accounts that were no longer on my computer. But it did not remove accounts I'm using in Outlook and OneDrive.
Step 1:
Close new Outlook. If it is running when you do the following steps, the addresses won't be removed.
Step 2:
Remove the accounts from Windows Settings > Accounts. Look under Email and under Work or School accounts. Remove or disconnect the accounts. Note: removing accounts here will sign you out of the account in Office and OneDrive.
Step 3:
After removing the accounts from Windows Settings, you need to delete the contents of this folder:
C:\Users\%username%\AppData\Local\Microsoft\OneAuth\blobs
Step 4:
Using Notepad, open each file in the following folder. Look for the email address for the account you want to remove. When you find a file with the address in it, delete the file.
C:\Users\%username%\AppData\Local\Microsoft\OneAuth\accounts
Tip: open Notepad on one half of the screen, the folder on the other half. Drag the files to notepad to view.
Step 5:
Finally, delete all the files in this folder:
C:\Users\%username%\AppData\Local\Microsoft\IdentityCache
Step 6:
Open new Outlook and open the Add account dialog.
It didn't work for me and the listed emails still appear.
Yeah, it doesn't remove all accounts. :(
YOU ARE AMAZING THANK YOU SO MUCH i was looking EVERYWHERE it finally worked!!! did exactly as you said
Thank you so much, I've been running in circles with other workarounds and this works. I really wish MS adds a way to delete accounts the user no longer uses/has access to from their sign in popup window thing on app based logins
Still doesn't work. New Outlook see all accounts and remember all cache about SMTP. My account doesn't work and even if I change my SMTP it still remember old one.
It picks up server names from autodiscover records in DNS.
Who is your email provider? If you are unsure what is the part of your address after the @ sign?
It doesn't work for me either. Found this, How do I remove suggested accounts from outlook? - Microsoft Community and someone suggested deleting C:\Users\ which seems very stupid thing to do as the directory contains lots of important files and folders.
It wouldnt be just C:\ users, it should be c:\users\%username%\... something else. The somewthing else shoud be what is in my article.
Note that it didn't work completely for me, removing some accounts but not others. I don't recall if it removed imap accounts from the list.
Handy if you change your email address in your existing account, works 100%
Perfect