So this one took a couple of days.
Long story short, This was showing up in the ULS logs:
SPUCHostService.exe (0x23E8) 0x17B4 SharePoint Foundation Sandboxed Code Service fe8a Medium – – Unable to activate worker process proxy object within the worker process
Did a little searching around, found this script. Still not totally sure what the ramifications are by allow full control of this registry entry and how insecure I’ve just made my environment, but long story short, it works!
$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