When I was in college, I entered a poetry contest. This was back in the day when I didn't have a personal computer of my own. I had to go to a computer lab to type up my poem and I saved it on a floppy disk.
Months went by and I didn't hear anything about my poem, so I assumed it sucked and that it didn't place. Then one day a check for $40 showed up in the mail with a letter informing me that I won the contest! I was thrilled and of course wanted to make sure I had a copy of my winning poem. When I went back to the computer lab to print off a copy, I discovered that my disk had a virus. The computer lab guys had to clean off my desk and my poem went with it. And just like that, the only copy of the poem I had was erased.
I tried to rewrite it, but have been unable to get it just the way it was before. I talked with the professors that ran the contest to find out if they still had my hard copy. No luck.
It was a hard lesson to learn but I usually keep hard copies of my writing now. And with the invention of cloud storage, I've got my stuff out there too as well as on a thumb drives.