Event ID 15001 when migrating mailboxes from 5.5

[mikevm]

When migrating from an Excahnge 5.5 erver to a 2003
server, (the 2003 is in a new org, new site) and using
the Migration Wizard to migrate mailboxes, I get an Event
ID 15001 in the Application Event log, and the mailbox
migration fails.

I am able to connect the mailbox to the AD user, the
migration wizard says the SID match. But the error is as
follows:

An account could not be created for
user'/o=<Orgname>/ou=<Sitename>/cn=Recepients/cn=<Username
>'

Any ideas what I should do/check?

 

[james3838]

Is there a contact with the same username?