If you have purchased a v6 to v8 upgrade or if your v6 license key has active support and maintenance, then you can upgrade your v6 installation to v8
- Your v6 installation needs to first be upgraded to v7.
See: Upgrading to Macrium Reflect v7 from an existing v6 Installation with active support & maintenance - Then you can upgrade your v7 installation to v8.
See: Upgrading to Macrium Reflect v8 with a v7 key entitled to a free upgrade