I had something worse than a license issue once..
Had a kid in his early 20s come into the PC shop I worked at practically in tears, it seemed his dad had FINALLY let him run the lumber mill for the first time while the old man went on his first vacation in 20 years...and the PC than ran the CNC that did custom columns went down and they had a contract worth tens of thousands that was gonna go belly up if they couldn't get the columns made!
The problem? The CNC system, which was this huge thing that cost them a couple hundred thousand back in the day...only worked with an ISA card plugged into a PC running Windows 3.1 and this was a year into Win 7 being out so needless to say no shops had Win 3.1 systems lying about and they needed the thing on THAT day! He had been to 2 other shops before he came into ours and was damn near in tears, told the boss the problem who replied "If anybody in town has something like that in would be my head guy,he's a packrat..YO GET UP HERE" and when he told me the issue and showed me the system I said "Yeah I got a couple of old 200Mhz with ISA slots back in my workshed at home but I'm kinda tied up here"...he just started throwing cash, gave the boss $250 just to "borrow" me for a couple hours, gave me $300 a pop for the 2 systems and another $350 to set them up by cloning his old drive to the "new" systems and making sure it all worked.
The moral of the story? If your butt depends on a crucial system? Best have backups. I ended up putting him in touch with an old engineer friend of mine (RIP David, you are missed) who built him a couple of serial port adapters that would take the place of the old ISA card if it ever goes tits up and last I heard that old CNC is still cranking out fancy columns using my old 200mhz workstation from back in the day.