Office 365 Migration – Transient error MapiExceptionLogonFailed has occurred

Office 365 Migration Error


We saw this error after the migration had processed around 50% of the migration batch, So we are using the same migration account, so how can it fail to logon ?

The error is a little misleading.

We tracked this error down to an issue with Server 2008 or higher where the number of AD logons per account is limited.

To resolve this issue:

edit the following registry key HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NTDS

Follow the instructions here: