One of our clients is a medical office practice, doctors and nurse practitioners and such. They use a program for their Electronic Medical Records, and the last update of that software introduced some "Undocumented Features" (we don't use the term "Bugs" because someone might get all butt-hurt and need a safe space... or something) that they've been fighting for a few months.
Vendor released a patch week before last that is purported to resolve the inconveniences caused by the aforementioned Undocumented Features, and it has fallen to me to install said patch.
Which I did last night.
Or, at least ATTEMPTED to do last night.
Because the server upgrade went fine, but every single client I tried up upgrade crashed. Hard.
So last night I was up until 11pm reverting their entire system back to the version with the Undocumented Features, and now I get to filter through one log file after another to find out what the hell went wrong.
Sometimes I loath this job.