Permissions error setting recovery option with changeserviceconfig2 - delphi

Question

I'm installing a service and wanting to set the service recovery options (using admin in an XP environment). I can change the description happily enough, but if the sfa.cActions is anything but zero it fails with a error 87 (parameter error).
//
// Actions to take on service failure
//
{$EXTERNALSYM _SC_ACTION_TYPE}
_SC_ACTION_TYPE = (SC_ACTION_NONE, SC_ACTION_RESTART, SC_ACTION_REBOOT, SC_ACTION_RUN_COMMAND);
{$EXTERNALSYM SC_ACTION_TYPE}
SC_ACTION_TYPE = _SC_ACTION_TYPE;
PServiceAction = ^TServiceAction;
{$EXTERNALSYM _SC_ACTION}
_SC_ACTION = record
aType : SC_ACTION_TYPE;
Delay : DWORD;
end;
{$EXTERNALSYM SC_ACTION}
SC_ACTION = _SC_ACTION;
TServiceAction = _SC_ACTION;
procedure TXyz_Service_Module.SetDescription(const Desc: ansistring);
var
hSCM: SC_HANDLE;
hService: SC_HANDLE;
sd: SERVICE_DESCRIPTION;
begin
hSCM := WinSvc.OpenSCManager(nil, nil, SC_MANAGER_ALL_ACCESS);
if hSCM = 0 then Exit;
hService := WinSvc.OpenService(hSCM, PChar(Self.Name), SERVICE_CHANGE_CONFIG);
if hService = 0 then Exit;
sd.lpDescription := PAnsiChar(Desc);
ChangeServiceConfig2(hService, SERVICE_CONFIG_DESCRIPTION, #sd);
WinSvc.CloseServiceHandle(hService);
WinSvc.CloseServiceHandle(hSCM);
end;
procedure TXyz_Service_Module.SetRecovery;
var
hSCM: SC_HANDLE;
hService: SC_HANDLE;
sfa: SERVICE_FAILURE_ACTIONS;
actions: array [0 .. 2] of SC_ACTION;
begin
hSCM := WinSvc.OpenSCManager(nil, nil, SC_MANAGER_ALL_ACCESS);
if hSCM = 0 then Exit;
hService := WinSvc.OpenService(hSCM, PChar(Self.Name), SERVICE_ALL_ACCESS);
if hService = 0 then Exit;
sfa.dwResetPeriod := 999; //INFINITE;
sfa.lpCommand := nil;
sfa.lpRebootMsg := nil;
sfa.cActions := 1;
sfa.lpsaActions := #actions[0];
actions[0].aType := SC_ACTION_RESTART;
actions[0].Delay := 5000;
(*actions[1].aType := SC_ACTION_RESTART;
actions[1].Delay := 5000;
actions[2].aType := SC_ACTION_RESTART;
actions[2].Delay := 5000;*)
if not changeserviceconfig2(hservice,SERVICE_CONFIG_FAILURE_ACTIONS,#sfa) then begin
showmessage('Error : '+inttostr(getlasterror));
end;
WinSvc.CloseServiceHandle(hService);
WinSvc.CloseServiceHandle(hSCM);
end;
procedure TXyz_Service_Module.ServiceAfterInstall(Sender: TService);
begin
self.SetDescription('Bananas are yellow');
self.SetRecovery;
end;

Answer 1

From the ChangeServiceConfig2() documentation:
hService [in]
A handle to the service. This handle is returned by the OpenService or CreateService function and must have the SERVICE_CHANGE_CONFIG access right. For more information, see Service Security and Access Rights.
If the service controller handles the SC_ACTION_RESTART action, hService must have the SERVICE_START access right.
So, SetRecovery() will need to use this at a minimum:
hService := WinSvc.OpenService(hSCM, PChar(Self.Name), SERVICE_CHANGE_CONFIG or SERVICE_START);

Answer 2

It's the enumeration value.
_SC_ACTION_TYPE = (SC_ACTION_NONE, SC_ACTION_RESTART, SC_ACTION_REBOOT, SC_ACTION_RUN_COMMAND);
needs to be
{$MinEnumSize=4}
_SC_ACTION_TYPE = (SC_ACTION_NONE, SC_ACTION_RESTART, SC_ACTION_REBOOT, SC_ACTION_RUN_COMMAND);
As recommended in the comments by David Heffernan.