A PowerShell function that sets the VM Tools Upgrade Policy on a VM. This function assumes you are using PowerCLI modules and are connected to a vCenter.

Set-VMToolsUpgradePolicy.ps1

#Requires -Version 3.0

function Set-VMToolsUpgradePolicy {

    <#
.SYNOPSIS
    Updates the Tools Upgrade Policy on VMware VM.
 
.DESCRIPTION
    This function uses get-view to get a managed object reference to a VM, and updates its 'ToolsUpgradePolicy'
 
.PARAMETER VM
    One or more valid vSphere VM objects.

.PARAMETER Setting
    This parameter can be either "manual", "upgradeAtPowerCycle"
 
.EXAMPLE
     get-vm | where name -like "myvm" | Set-VMToolsUpgradePolicy -Setting manual -verbose
  
.NOTES
    Author:  Jim Birley
#>

    [CmdletBinding()]
    [OutputType('PSCustomObject')]
    param (
        [Parameter(Mandatory, 
            ValueFromPipeline)]
        [PSCustomObject[]]$VM,
        [Parameter(Mandatory)]
        [ValidateSet("manual", "upgradeAtPowerCycle")] 
        [string]$Setting
    )

    BEGIN { }

    PROCESS {
        foreach ($MyVM in $VM) {
            Write-Verbose "Setting Tools Upgrade Policy on $($MyVM.Name) to $Setting"
            $MoRef = $MyVM | Get-View -verbose:$false
            $vmConfigSpec = New-Object VMware.Vim.VirtualMachineConfigSpec
            $vmConfigSpec.Tools = New-Object VMware.Vim.ToolsConfigInfo
            $vmConfigSpec.Tools.ToolsUpgradePolicy = $Setting
            $MoRef.ReconfigVM($vmConfigSpec)
            $MyVM | Select-Object Name, @{N='ToolsUpgradePolicy';E={($_ | get-view -Verbose:$false).Config.Tools.ToolsUpgradePolicy}}
        }
    }

    END { }
}