Sandboxed Solutions running SharePoint 2010 on a Domain Controller

If you're running SharePoint 2010 on a Domain Controller you need to add a ACL Access Rule to enable Sandboxed Solutions. Without this Acces Rule the Microsoft SharePoint Foundation User Code Service will start but the SPUCWorkerProcess.exe won't.

Run the following PowerShell command to fix this...

$acl = Get-Acl HKLM:\System\CurrentControlSet\Control\ComputerName
$person = [System.Security.Principal.NTAccount]"Users"
$access = [System.Security.AccessControl.RegistryRights]::FullControl
$inheritance = [System.Security.AccessControl.InheritanceFlags]"ContainerInherit, ObjectInherit"
$propagation = [System.Security.AccessControl.PropagationFlags]::None
$type = [System.Security.AccessControl.AccessControlType]::Allow
$rule = New-Object System.Security.AccessControl.RegistryAccessRule($person, $access, $inheritance, $propagation, $type)
$acl.AddAccessRule($rule)
Set-Acl HKLM:\System\CurrentControlSet\Control\ComputerName $acl