And if you ever modded your original Skyrim install, none of your saves from it will work. Blame the ease of Steam Workshop integration, blame the bugs, console-focused limitations and interface problems in the PC version - whichever, modding was both easy and appealing. This isn't much of a problem in consoleland, where modding wasn't really a thing, but over on a PC a great many of us chucked two, three or several dozen mods into our Skyrim installations. Unless, of course, you stick with the original version of Skyrim instead of the freshly-released The Elder Scrolls V: Skyrim Special Edition, or somehow never, ever added a mod to it. It's the end of the world as you knew it circa 2011-2013. You know that Skyrim savegame you invested hundreds of hours into? All those dead dragons, all those crafted weapons, all those mysteriously naked townsfolk? Gone, all gone.
Bad news, old chum, ol' pal, ol' mate of mine.