Question : What is the best way to find all records of an e-mail for our company?

I need to find all records of e-mail conversations that occurred between a couple company employees and an external user (e-mail). Is it possible to do that with Exchange System Manager. Also, I have collected all of the employee's .OST files. Any help will be greatly  appreciated. Is there any software that you recommend that does this. I tried looking in the list of Mailboxes that we have through Exchange Manger but with no luck.

Answer : What is the best way to find all records of an e-mail for our company?

Could you just open outlook as an admin user and add their mailbox to your outlook and then use advanced find to search for all emails where the to and from are the email addresses in question?