When installing and deploying Office Web Apps 2013 to a security hardened drive, Office Web Apps may not work correctly if there are permissions missing from the security hardened drive. The default location on most systems is the C drive, but some customers may install to non-system drives (such as a D drive, E drive, etc) and permissions may be stripped from those drives.
The Office Web Apps 2013 installer allows you to choose a path where the code will be installed, and non-system drives are supported. Also some of our configuration settings (such as CacheLocation) default to using the system drive, those can be overridden using the New-OfficeWebAppsFarm or Set-OfficeWebAppsFarm cmdlets. The Office Web Apps installation will still need to put a few small files in the %PROGRAMDATA% folder, which is typically on the system drive.
When deploying Office Web Apps 2013 to a hard drive that is security hardened (permissions are removed), the following permissions need to be present on the installation folders:
The “CREATOR OWNER” & “SERVERNAME\users” need permissions to the install location on the non-system drive:
Deploy Office Web Apps Server