usb - Why do all the directories on my tablet have all these weird numbers?

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Closed 7 years ago.

I have a Samsung Galaxy 10.1, running Android 3.2, which I've rooted.

When I plug it in by USB to my Ubuntu computer, it looks like this:

There's about 24 or so directories, all numbered as shown in the image. As far as I can tell, they don't correspond to any directories actually on the device, and I can neither find any files I think should be on the device or transfer any files to the device. (To be accurate: I can copy files to one of the weirdly numbered directories, but then I can't find them if I try to look for them from the tablet interface.)

What's going on, and, more importantly, how do I get a normal connection to my tablet so I can transfer files back and forth?

Update 1: I have learned this is probably "MTP mode". I can't seem to find any option to disable or change it.

Update 2: I have tried turning "USB debugging" both on and off, and neither way seems to make a difference.

Update 3: I've asked about this issue also on the Ubuntu SE site, in case part of my problem is on the Ubuntu side.

Update 4: Here's another error message I get if I try to use mtpfs to connect to the Android device: