You try to mount the VMware tools ISO but you get the following error.
Operation "Mount VMware Tools." failed for VM "MyComputer" for the following reason: The operation is not allowed in the current state.
Using the following command line to remove any existing ISO does not solve the problem:
Get-VM -Name MyComputer | Get-CDDrive | Set-CDDrive -NoMedia
Restarting the computer does not solve the problem neither.
What worked for me was to stop the VM and start the VM again.