I feel your friend’s pain. Anybody that has used a computer for any length of time, particularly in business or when giving presentations, has been in his shoes.
Let’s talk about some ways to avoid a repeat.
Don’t backup to thumb drives
First, don’t save to a thumb or flash drive over and over again. They wear out the more that you write to them. I consider them too unreliable to be the only place where you keep anything even halfway important.
I have had USB thumb drives die and they weren’t always inexpensive ones. I suspect that this happened to your friend.
My favorite backup technique these days is to place and edit my documents directly in their Dropbox folder. That way, Dropbox is more or less constantly updating the changed document every time I click Save. In my case, the document is uploaded to the internet as I work on it, but it’s also being mirrored on any machines on which I might also have Dropbox installed.
Now, some people don’t agree with this technique, but I’ve used it with success. In fact, I actually set it up so my wife does the same thing. When she’s working on a document, her default folder for Word and Excel files is a Dropbox folder. As she’s working, she can click Save and files are automatically replicated to our other machines.
In other words, they’re backed up.
Dropbox may even keep a certain number of history copies. That way it’s actually possible for you to go back in time on the Dropbox website.
Now I’ve mentioned Dropbox because it’s what I use and feel comfortable with, but there are similar tools that offer equivalent functionality.
It’s important to save on different types of media and locations than where that working copy is stored. This protects you from drive failure.
Other solutions include Auto Save and backup copies. I encourage you to make sure they are turned on. They all tend to save to the same drive, but they may help you recover from accidental deletions and changes.