As you are aware, we do not support NT authentication in V7.
In V8 the NT authentication method is completely different from V6.
Thus we are not able to update V6 (NT authentication) to V7 or V8.
Users might be able to manage/view the content.
V6 has been out of support for many years. The recordings are also not playable on new browsers.
V6 acm files should have been converted to acmx during V7.
Thus for this case, V8 has to be installed as new instead of over existing V6 folder.
If existing V6 recording is still needed, you can install V8 on another server.