Question : users can't make Internet Explorer their default browser after gpo installed firefox (user do not have admin rights).

users can't make Internet Explorer their default browser after gpo installed firefox (users do not have admin rights).

Answer : users can't make Internet Explorer their default browser after gpo installed firefox (user do not have admin rights).

You will have to run all these commands on the Exchange Server before the Installation.

http://technet.microsoft.com/en-us/library/bb125224.aspx

The Schema Version is Different for Exchange 2007 and it needs to be updated to Schema Version of Exchange 2010.

Usually these commands will be run by default when you run the Setup Wizard.