You have seen in the Postprocessing that it is possible to alter the data files as we like. Quite often it is required to keep the files intact and lock them for further processing. This can be achieved by opening the file, going to Setup and then choosing File locking. We can lock the files with a password which must be entered next time the file is opened or we can also lock the file permanently.
The file locking can be also enabled in the security in settings by default.