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MTP is utter garbage and belongs to the technological hall of shame.

MTP (media transfer protocol, or, more accurately, MOST TERRIBLE PROTOCOL) sometimes spontaneously stops responding, causing Windows Explorer to show its green placebo progress bar inside the file path bar which never reaches the end, and sometimes to whiningly show "(not responding)" with that white layer of mist fading in. Sometimes lists files' dates as 1970-01-01 (which is the Unix epoch), sometimes shows former names of folders prior to being renamed, even after refreshing. I refer to them as "ghost folders". As well known, large directories load extremely slowly in MTP. A directory listing with one thousand files could take well over a minute to load. On mass storage and FTP? Three seconds at most. Sometimes, new files are not even listed until rebooting the smartphone!

Arguably, MTP "has" no bugs. It IS a bug. There is so much more wrong with it that it does not even fit into one post. Therefore it has to be expanded into the comments.

When moving files within an MTP device, MTP does not directly move the selected files, but creates a copy and then deletes the source file, causing both needless wear on the mobile device' flash memory and the loss of files' original date and time attribute. Sometimes, the simple act of renaming a file causes Windows Explorer to stop responding until unplugging the MTP device. It actually once unfreezed after more than half an hour where I did something else in the meantime, but come on, who likes to wait that long? Thankfully, this has not happened to me on Linux file managers such as Nemo yet.

When moving files out using MTP, Windows Explorer does not move and delete each selected file individually, but only deletes the whole selection after finishing the transfer. This means that if the process crashes, no space has been freed on the MTP device (usually a smartphone), and one will have to carefully sort out a mess of duplicates. Linux file managers thankfully delete the source files individually.

Also, for each file transferred from an MTP device onto a mass storage device, Windows has the strange behaviour of briefly creating a file on the target device with the size of the entire selection. It does not actually write that amount of data for each file, since it couldn't do so in this short time, but the current file is listed with that size in Windows Explorer. You can test this by refreshing the target directory shortly after starting a file transfer of multiple selected files originating from an MTP device. For example, when copying or moving out 01.MP4 to 10.MP4, while 01.MP4 is being written, it is listed with the file size of all 01.MP4 to 10.MP4 combined, on the target device, and the file actually exists with that size on the file system for a brief moment. The same happens with each file of the selection. This means that the target device needs almost twice the free space as the selection of files on the source MTP device to be able to accept the incoming files, since the last file, 10.MP4 in this example, temporarily has the total size of 01.MP4 to 10.MP4. This strange behaviour has been on Windows since at least Windows 7, presumably since Microsoft implemented MTP, and has still not been changed. Perhaps the goal is to reserve space on the target device? However, it reserves far too much space.

When transfering from MTP to a UDF file system, sometimes it fails to transfer ZIP files, and only copies the first few bytes. 208 or 74 bytes in my testing.

When transfering several thousand files, Windows Explorer also sometimes decides to quit and restart in midst of the transfer. Also, I sometimes move files out by loading a part of the directory listing in Windows Explorer and then hitting "Esc" because it would take too long to load the entire directory listing. It actually once assigned the wrong file names, which I noticed since file naming conflicts would occur where the source and target files with the same names would have different sizes and time stamps. Both files were intact, but the target file had the name of a different file. You'd think they would figure something like this out after two decades, but no. On Linux, the MTP directory listing is only shown after it is loaded in entirety. However, if the directory has too many files, it fails with an "libmtp: couldn't get object handles" error without listing anything.

Sometimes, a folder appears empty until refreshing one more time. Sometimes, copying a folder out causes a blank folder to be copied to the target. This is why on MTP, only a selection of files and never folders should be moved out, due to the risk of the folder being deleted without everything having been transferred completely.

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