The C client is dead, and going forward VMware will no longer support it. I know there are still a lot of people using that old client, but its time to move on. I have known that this day was coming, and have been trying to only use the web client exclusively. Thankfully they are making a lot of changes. Such as no more Java or flash. Instead they are moving the web client to run on HTML5. The new version of the web client has been available as a fling for a while now, and since ESX 6 update 2 there has been a web interface for managing the host directly.
I think this is the right decision for VMware. Developing for both the C client and a web client; meant more resources were being used to accomplish the same thing. I hope other companies follow VMware and only use HTML5.