Before you install each server module discussed in this guide, set umask to 027 on the installation directory of that computer. Changing this setting eliminates other permissions, including group write permissions. This action also sets the default permissions, so that all of the files and directories that are created afterwards have rwxr-x--- permissions. The Siebel service owner account must have all permissions. However, the group must have read and execute (for directory access) permissions only. See also Creating the Siebel Service Owner Account.