How to get access to O365 mailbox after AD User account was moved to OU without ADConnect synchro-n

[freealkor]

Hello,

The Exchange set up is hybrid (on-premises Exchange server 2016 and O365).

Some mailbox was correctly created on the on-premises and migrated to online.

Some time ago the AD User account accidentally was moved to AD OU, that not included in Azure AD Connect synchronization.

Soon the user was disappeared in O365 Admin center.

Can I restore this online mailbox? How to do this?

Thank you in advance for any help!

Alex.

[#2 · Accepted solution]

Move the user back to the sync scope, force a sync. Now, if "some time ago" was over a month, you're out of luck (unless the mailbox was put on hold).