Hi All we are in the process of moving to a new exchange 2010 environment. currently we have a 2003 environtment which is very simple and runs all roles on a single box. we have a simple AD environment just 1 domain. we are moving to a new virtual environment 1 x virtual CAS/HUB server and 1 x virtual mailbox server. all is working correctly at the moment we can e mail from 2010 and have moved over a few user from 2003. what i have noticed is there is a big delay with e mail being sent from a user on 2010 to a user on 2003 ( approx 6-8 min delay). this only seem to be 1 way ( 2010 to 2003) as e mail from a 2003 user to a 2010 user are instant. i have done a bit of reading and not really found much information. I have done some basic things. i have added additional routing group connector but this has not made much difference. i have installed update rollup 4 and still the same. Im not sure if this is what is expected. i userstand there might be a slight delay routing messages between servers but would never have thought it would be about 6-8 mins. the users who are on 2010 user outlook 2007 as the client and the users on 2003 users outlook 2003 as the client. any help on troubleshooting this would be great Thanks in advanced

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