Spent most of the evening working with Norton Support last night on this edge case. After replacing an old/slow drive with an SSD, and using Recovery installation of 10.8, then a subsequent TimeMachine backup restore of 10.11, Norton Small Business will not install. The install fails midway through the installation - not the download. No workaround could be found, and it appears to be a sandboxing issue with Norton kext files. A Bare Metal installation of 10.11 does work, without a system image recovery from TimeMachine. Sequence is: 10.8 Internet Recovery Installation. Complete 10.11 download and installation, which will install on the Recovery Partition. Boot to Recovery Partition, erase the MacHD partition, and Install 10.11 from the Recovery Partition. Direct thumb drive installation of 10.11 failed repeatedly on boot strapping of the installer from the USB drive.