I have been accessing a VM on a host via the vSphere console with no issues and a few minutes ago started getting the following error when I tried to bring it up:
Unable to connect to the MKS: Login (username/password) incorrect.
I googled this and the references really didn't apply to this situation. This is on Esxi 5.5.0 and the host VM OS is W2008 R2. After rebooting the VM I am able to get in to it via the Remote Desktop Connection client.