With Enterprise Vault 9, a change was made in the Certification/Support matrix with regards to supported versions of Internet Explorer. As of Enterprise Vault 9, Internet Explorer 6 is no longer supported :
What this means is that if you have a server, where you wish to install Enterprise Vault, the following will happen :
You get to choose components, eg Admin Console, EV Services, then a deployment-scanner-esque set of checks runs, and you get an error if you have IE 6. The installer will then exit.
On a client, if you have IE 6 (on say Windows XP SP 2) when you try to install the Outlook Addin, the following happens :
The Addin actually installs. However, per the above chart you wouldn’t be supported/certified if you had to call Support.