Why can't I copy .zip files from a server to a server in a different domain?

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http://serverfault.com – At work, we're using a Windows Server 2008 R2 VM as our build server. At the end of the build process for any of our projects, we copy the packaged deployment files to a folder on the server where they'll be deployed. (This is done in a batch command by a service account.) For most of our projects, which deploy to a Windows Server 2008 R2 VM, this step goes swimmingly. But for one project, which deploys to a Windows Server 2003 R2 VM which resides in a different domain on our network, the .zip files return "Access is denied" and don't copy, though all of the other files copy correctly. O (HowTos)