Thought Feedback would be a more appropriate place to post this, as it's not a bug per se. Just a concern I wanted to share.
I've been using CCleaner for years. It's good at what it does and it does it easily and non-intrusively. That being said, the last update led to an unfortunate and somewhat devastating (perspective here people, stay with me) experience. One that isn't even really the fault of the software, but which directly led to spectacular human error.
I mod games. Lots of games. But for the purpose of this post, let's just give one - Skyrim. To the point, textures, meshes, scripts, and resources aside, mods are implemented by way of master and plugin files (.esm and .esp, respectively.) This is the mod "guts" itself. Without them, there are no mods (typically; sometimes texture swaps or quick fixes in a script don't have them, but the vast majority do.) Some mods require use of .dll files, such as script extenders, etc. Once you get a basic grasp on modding, it is not uncommon to have up to 255 mods or so active at any given time (or more if you are clever and can merge the .esp's.)
To the best of my knowledge, CCleaner - the registry cleaner specifically - has always done a great job cleaning up unused extensions and residual files left by programs after uninstalling them. And the software allows you to address each item one by one. But with dozens of actions being performed, it's impractical to do so, and most people mash their clicking finger on the option to address all of them at once. Which is normally good. Something went down behind the scenes of how it works this update though, because it wiped out all the .esm, .esp, and .dlls from their respective folders. And CCleaner never did that before. I didn't change any options, but the results changed from what they usually would be. And that's unfortunate. And I neglected to save a copy before doing it. Which is unfortunate and ironic - the software I use to keep the programs on my computer going smoothly caused the programs on my computer to stop working.
Now, like I said before, it isn’t technically the fault of the software. I should have backed up, and I should have tediously gone through each items one by one like a robot. But I didn’t because I had the expectation that the same maintenance I’ve done for years with the same software would likely yield similar results. It didn’t. So I wanted to share this with you in the hopes someone tweaked something in the update to be a little too overzealous in scanning and removing .esm, .esp, and .dll files. Hopefully this will prevent another avoidable Murphy’s Law situation by someone else.