Client 5.5 __link__: Vsphere
vSphere Client 5.5 is now (VMware ended general support on September 12, 2018). However, it remains in use for:
The internal rendering engine relies on legacy Internet Explorer components, causing performance degradation during script operations. vsphere client 5.5
As beloved as the C# client was for its speed, it had fatal flaws that led to its demise in later versions: vSphere Client 5