Messages sent to any Microsoft Email accounts (Outlook.com, Hotmail.com, Live.com etc.) from Vivaldi Email Service will not reach the destination account. There are no errors and the sent message from a Vivaldi email account does reside in the Vivaldi "Sent" folder - so there is every indication that the message was sent w/out any errors of any kind.
But the messages never reach the destination Microsoft email account's Inbox (and are not in any SPAM folder either).
So it would appear that Vivaldi email messages are getting blocked if sent to Microsoft Email accounts.
This issue has been tested by multiple users multiple times to confirm the issue that remains persistent for around the past 3 days as of ~2/23 (because I have personally sent messages this way on that day). The issue has been logged on the Vivaldi support forum as well.
Please advise. Thank you.