TerminateProcess not working for specific processes - c++

Question

I need to terminate some processes before my program can run, but whenever I run TerminateProcess(), GetLastError() returns 5. What I know so far is that this means that access is denied, I also know that to elevate my rights i need to use AdjustTokenPrivileges(), based on Rango's answer here and Microsoft's documentation here.
What i don't know is why it wont work. Based on what I've read, the following should work:
BOOL TerminateMyProcess(DWORD dwProcessId, UINT uExitCode)
{
DWORD dwDesiredAccess = PROCESS_ALL_ACCESS;
//DWORD dwDesiredAccess = ACCESS_SYSTEM_SECURITY;
BOOL bInheritHandle = FALSE;
HANDLE hProcess = NULL;
TOKEN_PRIVILEGES tp = { 0 };
LUID luid;
LookupPrivilegeValue(NULL, SE_SECURITY_NAME, &luid);
tp.PrivilegeCount = 1;
tp.Privileges[0].Luid = luid;
tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
AdjustTokenPrivileges(hProcess, FALSE, &tp, 0, NULL, NULL);
hProcess = OpenProcess(dwDesiredAccess, bInheritHandle, dwProcessId);
BOOL result = TerminateProcess(hProcess, uExitCode);
CloseHandle(hProcess);
return result;
}
As you can tell from the above, I am not sure which dwDesiredAccess I am supposed to use. PROCESS_ALL_ACCESS lets me terminate other simple processes, such as chrome.exe or notepad.exe, but not what i need to terminate. ACCESS_SYSTEM_SECURITY is whats' said to be used by microsoft, but then i cannot terminate any process at all.
Also, is this even close to what i need to do, if not can you please point me in the right direction.
UPDATE: Added UpdatePrivilege() function from here, and called it before calling OpenProcess() function, still no bite.
UPDATE 2: The process I need to terminate is the "afwServ.exe" process, i.e. Avast's firewall. I need to do this so that my firewall is the sole firewall used by Windows. This a requirement of my project.

Answer 1

I think you misunderstood the difference between right and privileges, this answer explains it.
In this case, your current user may not have permission to terminate the specified process. You may first need to use LogonUser and use administrator identity to simulate the process context.
What you want to terminate is a service, you can try using ControlService with SERVICE_CONTROL_STOP to stop the services. But you also need to switch to the user with permission first.