What's changed:
- Add early return when open existing config
fails due to different error than `ERROR_FILE_NOT_FOUND`
- Swich `ReadFileEx` to `ReadFile`
- Add `SetFilePointer` to make sure we're reading
from the beginning of the file
- Pass `overlapped` to `WriteFile` to make sure
we're writing from the beginning of the file
Related-To: NEO-8092
Signed-off-by: Fabian Zwolinski <fabian.zwolinski@intel.com>