DirHash | Windows command line utility to compute hash | File Utils library

When using both the lpApplicationName and lpCommandLine parameters of CreateProcess(), the lpCommandLine should include the EXE path as the 1st token in the command line. This is even stated in the CreateProcess() documentation:

If both lpApplicationName and lpCommandLine are non-NULL, the null-terminated string pointed to by lpApplicationName specifies the module to execute, and the null-terminated string pointed to by lpCommandLine specifies the command line. The new process can use GetCommandLine to retrieve the entire command line. Console processes written in C can use the argc and argv arguments to parse the command line. Because argv[0] is the module name, C programmers generally repeat the module name as the first token in the command line.

So, if you are going to include the EXE path in the command line, there is no need to use the lpApplicationName parameter at all:

If lpApplicationName is NULL, the first white space–delimited token of the command line specifies the module name. If you are using a long file name that contains a space, use quoted strings to indicate where the file name ends and the arguments begin (see the explanation for the lpApplicationName parameter )...

Also, rather than converting char strings to std::wstring (which you are not doing correctly) just to call CreateProcess() (which is being mapped to CreateProcessW() in this situation), you can use CreateProcessA() instead.

Try this: