Can I check please, which precise version do you have?
Version is 6.0.3b
I have made this slighty rough around the edges guide for you on this page http://zenar.io/upgrading-v6-v7 It should have all of the information for you, but understand that it's a justa quick guide, should you get stuck or have any questions please get in touch. Thank you.
Is there an upgrade process to upgrade a V6 multi-client site to V7 multi-client site?