In VMware vSphere, the VMX file is a configuration file that defines the settings and characteristics of a virtual machine. The VMX file is automatically managed by vSphere, and typically, you do not need to manually refresh or modify it directly. Instead, you interact with the virtual machine settings through the vSphere client or by using PowerShell cmdlets specifically designed for managing virtual machines.

If you need to update or refresh specific settings of a virtual machine, you can do so using the appropriate PowerCLI cmdlets. Here’s an example of how to refresh or update certain properties of a virtual machine using PowerCLI:

# Install VMware PowerCLI if not already installed
Install-Module VMware.PowerCLI -Force

# Connect to vSphere
Connect-VIServer -Server vCenter_Server_or_ESXi_Host -User username -Password password

# Specify the virtual machine name
$VMName = "YourVirtualMachine"

# Get the virtual machine object
$VM = Get-VM -Name $VMName

# Refresh the virtual machine configuration
$VM | Get-View | Invoke-VMScript -ScriptText "vim-cmd vmsvc/reload $($VM.ExtensionData.Config.UUID)"

# Disconnect from vSphere
Disconnect-VIServer -Server * -Confirm:$false

In the script above, we connect to the vSphere environment, get the virtual machine object, and then refresh its configuration by running a script inside the VM using Invoke-VMScript. The script inside the VM uses the vim-cmd command to reload the VM configuration.

Please note that refreshing the VMX file directly is not a common operation in typical vSphere management tasks. Most configuration changes are made through the vSphere client or using PowerCLI cmdlets like Set-VM to modify specific properties of the virtual machine. Manually modifying the VMX file is not recommended unless you have a specific need and understanding of the VMX file format and its implications.

Always exercise caution when working with virtual machines and their configuration, and ensure you have the necessary permissions and understanding of the actions you are performing. Test any script or operation in a non-production environment before using it in production.