Currently a mailbox for a synced user can be converted to shared in EAC. This results in a corrupted mailbox object and an Azure AD object that still requires a license. See https://support.microsoft.com/en-us/kb/2710029. Customers need to move the mailbox to on-premises Exchange, convert it to shared and then move the mailbox back to Exchange Online. This process can be cumbersome and even worse, if customer is not aware of this issue the shared mailbox will be removed after the grace period expires.

It should be supported to convert a mailbox to shared for a synced user in Exchange Online, or customers should be prevented from doing this and ending up in a bad situation by removing the 'Convert to shared' option in EAC for synced users.

Allow new "Guest User" entry to be converted to a different account type.

We have encountered the situation where a OneDrive share was granted to a user outside our tenant, which in turn then created this new "Guest User" entry in the system with the SMTP address. Later this user was requested to be added as a MailContact, but due to the fact the SMTP address existed already, it would not allow us to create. Deleting the user from Guest Users would remove all shared file access. Need a solution for this.

Issue
• You are unable to create a MailContact using the SMTP address of an external user that has already been added as a “guest user” to an Office 365 Group.
• If you create the MailContact first, you are able to add the same address as a “guest user”.

Cause
• You can only have one object in Exchange Online with a give primary SMTP address. This is because Exchange uses the primary SMTP address to route email to the recipient.
• If you add a “guest user” to an Office 365 Group, there has to be an Exchange Recipient object for that user. If there isn’t one, one will be created for you (RecipientType “MailUser”, RecipientTypeDetails “GuestMailUser”).

Workaround
• Delete the “guest user” MailUser object in Exchange Online
Get-MailUser username@example.com | Remove-MailUser
• Create the MailContact
• Add the MailContact to the Office 365 Group
Note: this is an issue, as the “guest user” may have already been granted access to multiple SharePoint resources and this will remove that access.

We have great trouble as we have "Poland" as our country in our organisation-profile and the VAT of our partner-companya in poland, and we can´t change that to "Germany" and to our VAT-No.
This should be possible what we see. A company could move to another country and so it should be possible to change a country and VAT for future (!) invoices.
Support tells me that the only actual way is to setup a new organization with our country, buy (!) the same stuff that we already have, backup anything localy in the old organization (wow, this means the whole Office365, Sharepoint and Azure stuff..., in a running organisation), and copy them to the new organization. I don´t see that we can do this, even if we get a refund for our already paid stuff.
Please have an indeed look what´s a realistic scenario for that.
We´re talking also about 2 EU-countries.
THANKS

GSuite accounts that are configured to send through Office 365 accounts via SMTP started sending multiple copies of the same email any time more than one domain name is sent to in a single email. For example you might send a sales update to 40 email addresses across multiple domains and each recipient will receive the same email 40 times. For further information on the issue please read this thread: https://answers.microsoft.com/en-us/outlook_com/forum/oemail-osend/multiple-copies-of-emails-sent-to-recipients-via/84cf9460-b7f4-4e6a-bf97-a115a825f369?tm=1538072613792

The only work around's are to BCC the group and put yourself in the To: field (no one gets duplicates but you) or you can take the time to log into the office365 account you are sending through and create a group email and add the email addresses you are trying to send to. This last method works with no problems but it is clunky for end users to setup so hopefully the underlying SMTP malfunction will be fixed soon.

Thanks

When a number of "user created" exchange folders were hard deleted by mistake, we opened a premier case - 116120615030507. To make a long story short, we found out that there is no exchange backup of the exchange mailboxes in this case. If items are accidentally hard deleted by the customer, there is no recovery of the mailbox. This is a worse situation than we had on premise, where we could restore mailboxes.

Accidents happen, nobody is flawless and and you have to be able to restore from backup. We actually had to use a combination of mfc mapi and compliance center to restore the data on a one by one basis for a number of users, but clearly this method would not scale if a LOT of mailboxes or folders were wiped out. If an organization lost ALL of its email though a large mistake/hard delete, how would they recover all of the data quickly without an exchange backup? As a “cloud” company, “cloud recovery” should be offered. A one by one Compliance center manual recovery would not do it for large organizations, not to mention - user created folder structure is not saved in compliance center. "Cloud" should not add layers of manual management, or require 3rd party backup software.