Good evening, Is it okay to run setup /pl after initially installing only Exchange 2010 servers in a new forest and then deciding that I do in fact need to install an Exchange 2003 server in that same forest. Will the legacy perpmissions be applied correctly, will interoperarbility between Exchange 2010 and Exchange 2003 work or will I need to correct things afterwards? Non-Microosft please comment only if you have specifally run into this same situation and put in an effort to make it work. Microsoft please comment with the answer from a member of the Exchange team. The domain is too far down the road to have to start out again so I would to make this work but if it isnt possible then I need to change course now. Thank you. IPack

Hello Yes i agree with Tim you cannot install the legacy exchange in existing Exchange 2010 topology because its now considered a pure Exchange 2010 organization.Thanks Mouzzam Hussain Visit to my Blog mouzzamh.wordpress.com