> is now normal corporate procedure to permanently erase emails after x days.
This has not been my experience.
I have worked for four $1bn+ hi-tech corporations, and we are required to keep every project-related, and policy-related email. Just to be sure, IT backs everything up periodically and puts it into long-term storage.
This practice has spared the corp from patent and copyright challenges, and has provided evidence in its challenges, on several occasions.
GD Land Systems made this policy after the Microsoft debacle. If you’d read some of the astonishing things their managers said in writing you’d do the same. I’d read it was (at least at that time) becoming the standard.