>> One of our customer required perfect uptime

In all honesty, these are the kind of clients I politely point at someone else. They seldom have the resources to fund the requirement, and one absurd requirement leads to another.

I'm sure they had good reason, and good on you for pulling it off, but trying to keep Windows 3.1 up for multiple years sounds like a risky task to take on. Who knew there wasn't another time-sensitive bug in there that kicked in at say 365 days?

To be fair the insane requirements I've come across are just delusional so they're easy to walk away from.