Why does Plex chew up space on my C:/ (OS) drive when I installed it to A:/ on Win 10 Pro

Took some time before deciding on software to manage my media files and choose PLEX.

I have a brand new rig, with a M.2 SSD for my OS, a few other Samsung 950’s for games and applications where I installed PLEX to A:/

All my media is on a 2TB Raid 1 Volume on S:/

As I added the two directories with photos and music to the library which again resides on S:/, I have noticed PLEX is eating up a ton of space already as it “processing” the files. Over 3GB so far and counting…

How do I move whatever is caching thumbnails/metadata/etc to my A:/ drive and off my system drive?

It’s quite ridiculous that when you do a custom install and specify which drive to install your application it decides can write to an unspecified directory during the install.

I was this > < close to buying a lifetime sub, but not so sure now.

5 GB gone now ffs

I’m not certain this is the problem, but drive letters A and B were historically reserved for floppy disk drives. As such, system BIOSes and operating systems, including Windows, treat them differently, especially when it came to indexing and caching, even if they aren’t floppy drives. It may be that your operating system simply won’t use the A drive for caching, and it has nothing to do with Plex.

Plex wants to be installed on the OS drive… I guess you found that out. The PMS itself isn’t very big and it really wants to be on the OS drive. It’s serious about it.

You can change the path where local application data is stored however. It’s cryptically called The path where local application data is stored - Plexweb/Settings/General/The path where local application data is stored

Here’s the deal. If you don’t want to start all over follow these instructions to the letter:


and be prepared to start all over because right in here is where sh*& happens.

The good news is that after you do this when the OS goes belly up taking Plex along with it it’s a simple matter to fix the OS, reinstall Plex and aim it back at The path where local application data is stored.

Happy New Year.

Historically, floppy drives have been obsolete for 20 years +

I don’t think this is the issue.

Thanks Tony

No Problem… Welcome to the forum.

You can set environmental variables to cache wherever you desire you data to be…for windows at least. Thanks to Tony for pointing out how/why Plex makes things difficult.

@jculotta@gmail.com said:
Historically, floppy drives have been obsolete for 20 years +

I don’t think this is the issue.

Doesn’t mean they’ve been written out of operating system code.

@jculotta@gmail.com said:
5 GB gone now ffs

So… even if you had to start all over now is the best time. Last I checked my data directory was a paltry 95GB and safely tucked away on F:/

This location we’re talking about most definitely needs to be on a local drive and I think the instructions make that pretty clear. Read the whole thread. There are some juicy bits down the page.

Awesome - even after uninstalling the App and rebooting, the crap it decided to write to my AppData/Local/Plex Media Server persists.

■■■■ off Plex - hello Kodi

If you changed the path where local application data is stored and there’s stuff going in it - delete the old data directory. If you’re in a ‘reinstalling’ mode be sure to install it on the OS drive. I think the next update will put it right back there so go ahead and cut to the chase scene. As I said it’s not very big and it really wants to be on the OS drive. I mean really.

Typically Plex doesn’t remove stuff. Sometimes that’s good - like when you bork this move and have to start again, but if you’re good to go, whack it.

Your insight and input is very helpful Tony - thanks for taking time to assist.

Being I just installed today and wanted to start fresh, I uninstalled Plex (didnt changed paths within the app prior, only during install), seemingly with no issues - until I saw the drive space eaten up was not released.

I had to manually navigate to the location (made easy with WinDirStat), and delete the 300k files + 5G of thumbnails it decided to write to C:/ - my precious M.2 OS drive.

I will reinstall and give plex another try…configuring the local app data to store where I desire and see what happens.

These are all local drives btw - not mapped/shared/external

Yea, that’s the ticket. Before starting to add anything make sure Plex is aimed at the new folder. Mine’s called:
F:\Plex Server Files
no trailing slash. Do create that folder though. Just aim Plex at it.

WinDirStat? Is that anything like Windows Explorer?
(The beauty of Plex is that even idiots like me can use it - but there are times I’m glad I know who to ask when it blows up)
:slight_smile:

BTW. Since I am an idiot, (previous disclaimer) Plex may write enough into that location on the OS drive so it can get it’self started (you know, maybe even the path where local application data is stored), but once you start adding stuff all the thumbs, artwork, log files, previous versions (very handy), etc are out there on another drive.

WinDirStat gives you a really nice, navigable, color-coded view of whats occupying space on your drives.

Thanks again - happy new year sir!