I happened to have the need to search a journal archive the other day for a particular message. I actually had useful information about the message, including the message ID. No problem to search on that, or so I thought!
Quite some time ago I wrote about how to search based on message ID. But I could not get it to work on my Enterprise Vault 10.0.4 Environment. I tried another in a different lab, and it has the same problem. I even tried an Enterprise Vault 9 lab environment, and that worked. I thought “Ahhaa I’m on to something here”. And I was. There is a known issue in Enterprise Vault 10.0.4 that affects searching by message ID, if the index is a 64 bit (which in my case it was). It is nicely documented in this article:
Definitely worth remembering if you do this sort of thing.