sbs2003 to sbs 2011 migration

We are doing a migration from sbs2003 to sbs 2011.

We are ready to uninstall exchange from the sbs2003 server but when we go to add/remove and hit the change/uninstall for sbs2003 it opens, shows a number 2 in the progress bar then closes back to the add/remove program screen.

I want to remove exchange 2003 the proper way if possible.

Anyone see this before?

Thanks

Joe