Ahhh UPS issues...
About 10/12 years ago, I was a regular on site to a particular council in Devon.
It was a relatively small council in the grand scheme of things, but it does still have a higher-than-average anecdote count, compared to other sites I worked at.
Anyway, the company I worked for had put in a load of new racks, with new servers and a meaty HP UPS - a 6.5kVA unit if I recall.
The council sparky had run the requisite 40A commando socket and the UPS was installed, followed by the big-as-houses batteries (they certainly felt that big and heavy!).
All final checks done, power to the UPS and... the main breaker to the entire building was tripped.
Sparky does some checks. Nothing apparently out of order. Power back on, power to the UPS...tripped.
Turned out to be a faulty UPS.
But now the fun and games began, including tracking down the voicemail server.
Eventually someone from the post room that had been there for years and years overheard and happened to ask if we meant a computer? Yes..yes we did, why?
He took us into the post room and pointed us to a huge pile of hessian sacks in one corner.
Underneath it all (literally buried under about 4ft of them!) was an ancient Compaw ProSignia server.
We powered it on - Netware 3, baby, which was old even then.
Most things came up but the VM system was still down.
The head of IT called the company who supported the machine only to be told they'd basically no idea who we were, and did they really support it? Gosh!
Eventually the admin password was traced (a very techie ncc1701d) and we were able to log on and start the VM NLM.
We tried to work out, but we believe that that server had survived with near zero air flow for around 7 years.
I loved working at that place, even if the driver there and home was an absolute bitch.