Internal mail flow for an Exchange Server environment can be broken due to a number of common mis-configurations.
A look at the Office 365 Support and Recovery Assistant (SaRA) diagnotic tool from Microsoft.
The confusion over disabling an Exchange Server mailbox vs removing a mailbox could be easily solved with two simple changes.
Understand the issues that cause Exchange Server databases to fail to mount due to corruption and dirty shutdown states.
In this episode of the Exchange Server Pro Podcast, Andrew Higginbotham and I discuss the new Exchange Server Troubleshooting Companion eBook.