Cheat Engine

[Moon]

These days, I'm trying to rewrite dbk32_function.pas in C++ in order to make a DLL. But I met a problem.

When deviceiocontrol function is called for the first time in InitializeDriver function, It fails with error code 31, ERROR_GEN_FAILURE

The description for this error is;
"A device attached to the system is not functioning."

I checked several points. registry and logical file and some handles. But it doesn't seem to have problem.

I have no further idea to find the problem. Is there anything else I can do?

[Dark Byte]

the device driver service is properly registered and running ?
And you did get a valid handle when opening it ?

And ioctl is build up properly?

[Moon]

Thank you DB.

I found that the StartService function fails with an error :
ERROR_SERVICE_ALREADY_RUNNING

But the StartService function wasn't called before.

The code flow is like following:

hSCManager = OpenSCManager(0, 0, GENERIC_READ | GENERIC_WRITE); (success)

hService = OpenService((SC_HANDLE) hSCManager, (LPTSTR) servicename.c_str(), SERVICE_ALL_ACCESS); (success)

ChangeServiceConfig((SC_HANDLE) hService,
SERVICE_KERNEL_DRIVER,
SERVICE_DEMAND_START,
SERVICE_ERROR_NORMAL,
(LPTSTR) driverloc.c_str(),
0,
0,
0,
0,
0,
(LPTSTR) servicename.c_str()); (success)

StartService((SC_HANDLE) hService, NULL, NULL) (fail)

And the registry status is like attached image.

[Dark Byte]

If it is already started then there is no problem, just continue.