When trying to connect to the VMware vSphere console you can get the following error:
Unable to connect to the MKS: Console access to the virtual machine cannot be granted since the connection limit of 0 has been reached.
This can be caused by a number of things and fixed in a few different ways.
Fix one is to edit the RemoteDisplay.maxConnections in the vmx file of the VM giving the Unable to connect to the MKS error to increase the connection limit.
Fix number two is to shut the VM down, edit the settings of the VM, click the Option tab, select Advanced -> General and click the Configuration Parameters… button. Then click Add Row and add RemoteDisplay.maxConnections with a value of 10.
Finally, you can fix the connection limit of 0 has been reached error by logging onto the vSphere web client (https://vCenterIP:9443/vsphere-client), right clicking the VM and clicking Configuration -> Edit Settings… On the VM Options tab, expand VMware Remote Console Options and set Limit the number of simultaneous connections to this virtual machine to 10 (you can also try removing the tick in the box if there’s one there – the default is set to 0, which would account for the connection limit of 0 has been reached error).