A few years ago I was asked to build a database in Excel which would import spreadsheets that clients submitted, accumilate all that data then spit out a whopping great big CSV file every month. And the most insulting thing of all was that I had to build this abomination using VBA macros so I could guarantee that the CSV output was clean enough to be exported into an Oracle RDBMS we also ran. I frequently raised the point that we should be running all of our databases on Oracle, but I was refused every time (I could write a whole essay on their dumb rational behind this, but that's another rant entirely).
So off I set writing one of the most complicated Excel macros of my life (and wondering what I'd done in a past life to be lumbered with such moronic management). I wrote every piece of data cleansing I could imagine knowing full well that the spreadsheets our clients would be submitting are bound to have had their formatting messed around with (and trust me, I tried everything I could to lock that template spreadsheets down). Yet, and without fail, every month at least 10 spreadsheets would be rejected from my macro's import routine because the data was so garbled that it was beyond cleansing.
Usually it was a simple job to fix the spreadsheets - or a simple phone call to the client where I verbally slapped them as much as I dared; vainly hoping that might serve as a warning to them that they shouldn't be cocking about with the layout of the template. Needless to say, it never had any affect.
However this one time I was completely baffled. The spreadsheet look fine at first glance, yet my routine rejected it. Sure, I couldn't click inside any of the cells, but the spreadsheet was locked from editing so that was to expected......or was it?
It turned out that the idiot who submitted that spreadsheet printed out their completed template, then scanned it in on a MFD (a scanner with bells and whistles). Then got that MFD to e-mail them a PDF of the printed page and now scanned page so that they could then embed that back into the fucking template.
All I asked them to do was fill a couple of columns of data then e-mail me the spreadsheet as an attachment. But nothing is too simple when you're dealing with users who think they understand computers.