Question

How to set a binary registry value (REG_BINARY) with PowerShell?

Background:

I need to change some properties of the ASP.NET State service using a PowerShell script. Unfortunately, the built-in PowerShell cmdlet Set-Service only lets you modify the service description, startup type, display name, and status. I need to modify the Subsequent failures property found on the Recovery tab (when viewing the service’s properties). I found that this value was stored in the registry as a REG_BINARY value.

An export of the value looks like this:

[HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\services\aspnet_state]
"FailureActions"=hex:50,33,01,00,00,00,00,00,00,00,00,00,03,00,00,00,0e,00,00,\
  00,01,00,00,00,00,00,00,00,01,00,00,00,00,00,00,00,01,00,00,00,00,00,00,00

In Powershell there is a Set-ItemProperty cmdlet with which you can set registry value values. For a string or dword value, you can just pass a string or an int. I know which hex value in the array to change, but I can’t figure out how to set a binary value.

Answer 1

The following line gives you an example how to create one

New-ItemProperty -Path . -Name Test -PropertyType Binary -Value ([byte[]](0x30,0x31,0xFF))

and how to change an existing one:

Set-ItemProperty -Path . -Name Test -Value ([byte[]](0x33,0x32,0xFF))