Everything on a computer is stored somewhere. And it might take a little time to determine where E-mail addresses etc. are being stored. But it is usually worth the effort if you consider your work to be important.

On my own computers I always create a special C:\ Super Directory in which I store everything that I possibly can. I also have a high capacity USB linked external drive. And now and then I tell my primary computer to simply copy the entire Super Directory to the external drive. It takes it an entire day to copy all of the files at the slow USB speeds. But it is nice to know that nothing will be lost in case of a main computer disk failure etc.