[MHK]

Hello everyone,

I had the same issue as Incanus but I found a workaround that does not require you to move your files temporary. And just need to be done once.
To give a bit of context: I use Calibre-portable 8.6 and I want to send content in my phone that has a SD card that was pretty big with cbz and png (around 200G)

Steps.
1. I remove my SD card from my phone
2. I connect my phone to Calibre and I wait for the process to finish.
3. I find the configuration file "mtp_devices.json" : goes to Preferences > Miscellaneous > Open folder (or Open configuration folder)
4. I close Calibre.
5. I disconnet my phone from the computer.
6. I open the configuration file "mtp_devices.json" with a text editor
You now have a file that look like this :

{
  "blacklist": [],
  "device-XXX": {
    "ignored_folders": {
      "s10001": [
        "folder1",
        "folder2",
        "folder3"
      ]
    },
  },
  "history": {
    "XXX": [
      "Name of your device",
      "date-hour of connexion"
    ]
  }
}

6. I edit this with the additional

"s20001": [
    "folderX",
    "folderY",
]

(don't forget any ',' or [] or {})

Notes:
- If you have several devices in your history, you need to edit the ignored_folders of your desire device.
- If you want to ignore all folder of your sdcard, you have to add all of the folder name (first level) under "s20001" section. In lower case. Don't forget hidden folder.

7. I save the file and I close it.
8. I open Calibre.
9. I put SD card in my phone.
10. I connect my phone to my computer.
11. Now, Calibre only scan the primary memory of my phone (as I choose to ignore all the folder on my SD Card) I can now send content on my phone (either on Primary Memory or card)

Notes:
- If you have a new folder at the root of your SD card that you want to ignore, you can go to edit the ignored folder directly on Calibre if it's not too big to scan (or edit the same file "mtp_devices.json" before connecting your phone to Calibre)

Here is an edited exemple of my configuration file.

{
  "blacklist": [],
  "device-XXXXX": {
    "format_map": [
      "epub",
      "cbz",
      "kepub"
    ],
    "ignored_folders": {
      "s10001": [
        "download",
        "documents",
        "podcasts"
      ],
      "s20001": [
        "download",
        "documents",
        "recordings",
        ".android_secure",
        "podcasts"
      ]
    },
    "rules": [
      [
        "epub",
        "Books/"
      ]
    ],
    "send_template": "{author}_{series:re([\\s'],_)||_}{series_index:||_}{title:re([\\s'],_)||}",
    "send_to": [
      "Books/"
    ]
  },
  "history": {
    "XXXXX": [
      "Phone of MHK",
      "date-time "
    ]
  }
}

I hope this help !

PS. If your SD card is not recognized as "s20001" , I have a way to maybe find what it can be. (This may not work but this would be the way I find mine) So ask away if it's not recognized as "s20001"