Often we get asked how to troubleshoot Enterprise Vault for SharePoint issues, so here is a little bit of information. A good starting point is to check:
How to check that the Enterprise Vault SharePoint components are installed and configured on the SharePoint Web FrontEnds. http://www.symantec.com/docs/HOWTO60773
This will help you ensure you have the necessary components.
When installing, you want to make sure you are logged in as the Farm Admin account (or an account with proper permissions per the guide), however, when you run the SharePoint Configuration you want to be logged in as the Vault Service Account.
Dtraces will often help, though many people do not know what to dtrace. On your SharePoint FrontEnds you will want to dtrace AdminService for sure. On the EV server you can dtrace EVSharePointArchiveTask.
SharePoint Designer can also be helpful for looking at archived item properties should you need to.
