This has nothing to do with EERM, DLP or McAfee. It's an issue in Win 7, specifically with SMB 2 and queries to the NTFS extended attributes.
I've seen this problem with no third-party software installed. If you copy files to a 2003 server you won't see the problem, only when copying between Win 7 and 2008 server.
You should open a ticket with Microsoft as well.
We've been using Windows 7 and 2008 server without any issues.
Once McAfee DLP is installed on the Win 7 x64 machine the performance issues start to happen immediately including browsing the internet, not just file shares. Once the DLP software is removed from Win7 x64 performance is restored to normal.
Have you successfully deployed DLP 9 on Windows 7 x64?
I have deployed it to Win 7. We don't have any production 2008 servers. All of our servers are 2003.
DLP stores tags in the NTFS extended attributes. Any software that accesses/queries the extended attributes will expose this issue in Win 7/2008.