char *filename;

////

LPWSTR lpwstr_filename;

int slen = MultiByteToWideChar(CP_ACP, 0, filename, strlen(filename), NULL, NULL);

lpwstr_filename = SysAllocStringLen(NULL, slen);

MultiByteToWideChar(CP_ACP, 0, filename, strlen(filename), lpwstr_filename, slen);

SysFreeString(lpwstr_filename);