Please ensure that you have the new license prior to upgrading.
Request your new 7.0 license here
From the dropdown menus select the following:
How can we help you? "Request a license key for a new version or upgrade"
Product "syslog-ng Store Box"
Post-upgrade reboot there will be a message "No license is available" in the SSB GUI.
Install your new license from the SSB GUI here: Basic Settings -> System -> License -> Upload new license file.
Please review the documentation prior to upgrading.
The documentation of the Syslog-ng Store Box is available here
Firmware and other files for Syslog-ng Store Box are available here