I'm trying to convert email from a generic IMAP server to Exchange.

I get random errors in doing so. For no aparrent rhyme or reason the process
just drops certain emails.

I've set all the size limits to "unlimited" in Exchange / AD IP Site Links

I ran the command from the shell in verbose mode and received this error
(redacted)

WARNING: An item has failed property validation and will be ignored.
Identifier:(Name:[Subject]) Error details:Required property is empty.
Property:TargetServer..

This does not happen on all mail, however, the fact it is not predictable
makes the planned conversion to Exchange 2007 very problematic and
politically untenable.

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