Issue: event ids 7001/17106
Transport Mail Database: MSExchangeTransport has detected a critical storage error, updated the registry key (SOFTWAREMicrosoftExchangeServerv14TransportQueueDatabase) and as a result, will attempt self-healing after process restart.
The transport service will be stopped. Reason: A failure occurred in a transport database operation.
remove old queue database
restart transport service
Mail started flowing