Registry: Delete key for each local user within system - c++

Question

I got a certain registry key (created by our software) which needs to be removed on each local user account at some point.
Thus, I try to load the users hive and then use SHDeleteKey (as the key is not empty) to get the job done.
However, SHDeleteKey always returns LSTATUS 2 (ERROR_FILE_NOT_FOUND).
The Registry key for each user is placed under
HKCU\Software\XYZ
First, I set the required privileges within my code, which seems to work (return val is TRUE):
(...)
HANDLE th;
LUID rsto;
LUID bckp;
TOKEN_PRIVILEGES tp;
TOKEN_PRIVILEGES tp2;
OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &th);
LookupPrivilegeValue(NULL, SE_RESTORE_NAME, &rsto);
LookupPrivilegeValue(NULL, SE_BACKUP_NAME, &bckp);
tp.PrivilegeCount = 1;
tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
tp.Privileges[0].Luid = rsto;
tp2.PrivilegeCount = 1;
tp2.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
tp2.Privileges[0].Luid = bckp;
BOOL p = AdjustTokenPrivileges(th, 0, &tp, 1024, 0, 0);
BOOL p2 = AdjustTokenPrivileges(th, 0, &tp2, 1024, 0, 0);
(...)
Then I use RegloadKey to load the users hive.
std::string connection contains the path to the respective ntuser.dat file. username is the local user account name.
So the hive should be loaded under HKEY_USERS\username:
(...)
DWORD result = RegLoadKey(HKEY_USERS, username.c_str(), connection.c_str());
return result == ERROR_SUCCESS;
(...)
Now, I try to delete:
(...)
k = username + "\\Software\\XYZ";
result = SHDeleteKey(HKEY_USERS, k.c_str());
And now result has value of 2.
But the key exists.
What am I doing wrong?
Thank you in advance...
UPDATED INFO:
I realized the problem needs to be somewhere on RegLoadKey.
When I load the hive via command line (REG.exe load "HKU\username" ...), I can see the node "username" under HKEY_USERS within regedit.exe. All child nodes are loaded under that node.
When I pause my program after RegLoadKey, the node "username" is also shown under HKEY_USERS, but the node is visualized as empty, so no child nodes are available.
How can this happen? This problem is driving me nuts.

Answer 1

Looked at my code again today and I just saw that I loaded "ntuser.BAT" instead of "ntuser.DAT" (both files exist).
I'm really sorry that I wasted your time. :-/