I've installed a test platform of migration from 5.5 to 2K3.
My 5.5 organisation contains several sites hosted in different NT4 domains connected through trust relationships.
The test platform simulates 2 sites in 2 domains (NT4 SP6 - Exchange 5.5 SP4). I tried to migrate one of them.
The migration from NT4 to Windows 2003 has been done without any problem (installation of a new machine, promotion as NT4 PDC of the domain, then upgrade to W2K3).
I launched on the Windows 2K3 the Exchange 2K3 wizard, and choosed to install a new Exchange 2003 on a site having a 5.5 server.
The wizard ran without any error in logs, and I could launch post install tests that returned successful logs.
Problems began when I restarted the server : all Exchange services started except the SRS.
There are lots of errors and warning in the Application Event Viewer. Hereafter are first logged just after the reboot (only errors and warning) : some of them were logged several times:
MSExchangeAL (error) - LDAP Operations - 8026 : LDAP bind was unsuccessful on directory dedomc.de.cast.com for distinguished name ''. Directory returned error (0x51) Server Down.
MSADC (error) - LDAP Operations - 8026 : LDAP bind was unsuccessful on directory dedomc.de.cast.com for distinguished name ''. Directory returned error (0x34) Unavailable.
MSExchangeAL (error) - Service Control - 8026 : The WIN32 API call 'DSGetDCNameW' returned error code (0x826). The specified component could not be found in the configuration information. The service could not be initialized. Make sure that the operating system was installed properly.
MSExchangeSRS (warning) - Service Control - 1403 : Site replication service was unable to obtain legacy account details and cannot continue.
FYI : de.cast.com is a child domain of the win2000 domain cast.com which had been forest and domain "preped" (from 2K3 CD).
I ran the full test twice from scratch with the same behaviour.
Thanks for your help.