• This issue occurs when a virtual machine is running on an ESXi 5.1 host build 1743533.
• The VMware guest customization runs each time the virtual machine is power cycled and may remove previously configured settings.
• The VMware guest customization runs if virtual machine hardware is modified and may result in an unexpected virtual machine reboot.
• The guestcust.log file (located at C:\windows\temp\vmware-imc\ on the virtual machine) contains this error:

Unable to set customization status in vmx.

1. Open vSphere PowerCLI.
2. Connect to the vCenter Server or ESXi by running the command:
   
   Connect-VIServer FQDN_or_IP_of_VC_or_ESXi
   
   
3. Find the virtual machine name by running the command:
   
   Get-VM | select-string Partial_virtual_machine_name
   
   
4. Using the virtual machine name found in step 3, delete the tools.deployPkg.fileName parameter by running the command:
   
   Note: The two single quotes in this command delete the value.
   
   Get-VM virtual_machine_name | Get-AdvancedSetting -Name tools.deployPkg.fileName | Set-AdvancedSetting -Value '' -Confirm:$false

• Run this command to make changes in each affected virtual machine on vCenter Server that you are connected to:
  
  Get-VM | Get-AdvancedSetting -Name tools.deployPkg.fileName | Set-AdvancedSetting -Value '' -Confirm:$false
  
  
• Run this command to make changes in each virtual machine in a given cluster:
  
  Get-cluster -name ClusterName | Get-VM | Get-AdvancedSetting -Name tools.deployPkg.fileName | Set-AdvancedSetting -Value '' -Confirm:$false
  
  
• Run this command to make changes on all virtual machines on a certain host:
  
  Get-vmhost -name host.domain.local | Get-VM | Get-AdvancedSetting -Name tools.deployPkg.fileName | Set-AdvancedSetting -Value '' -Confirm:$false

1. Power down the virtual machine.
2. Right-click the virtual machine and click Edit Settings.
3. Click the Options tab > Advanced (General) > Configuration Parameters.
4. Locate the tools.deployPkg.fileName parameter, double-click its value and delete it.
5. Click OK and OK again to save the change.
6. Power on the virtual machine.
   
   

1. Power down the virtual machine.
2. Right-click the virtual machine and click Edit Settings.
3. Click the Options tab > Advanced (Configuration Parameters) > Edit Configuration.
4. Find the tools.deployPkg.fileName parameter, double-click its value and delete it.
5. Click OK and OK again to save the change.
6. Power on the virtual machine.