Can't move files to usb drive

[cm-mc]

Android 10, one UI 2.5
v.1.7.2
Root auto
Can access source and destination (through paragon app), but can't move files from sd card to usb drive (there's disk activity, but nothing happens after selecting destination).

[Feuerswut]

Does the app have write access to the USB device, it may have to be granted after plugging it in. (each time)

[cm-mc]

Yes, and i can read the device alright; the permission is granted to content://com.paragon_software.documentproviderserver.documents/tree/root; this works on every other app (fx, x-plorer, mixplorer, even android file transfer app). Anyway, just tried again with just one file (instead of dozens), and without any settings change, and it worked; maybe there's some file number/total file size limit?

[Feuerswut]

Yes, and i can read the device alright; the permission is granted to content://com.paragon_software.documentproviderserver.documents/tree/root; this works on every other app (fx, x-plorer, mixplorer, even android file transfer app). Anyway, just tried again with just one file (instead of dozens), and without any settings change, and it worked; maybe there's some file number/total file size limit?

This isn't paragon explorer.
The app id is com.zanghai.materialfiles

This app needs to be granted access via the android documentsui (default file picker) to the usb stick.

make a screenshot of the error you encounter please and provide it here.

IMPORTANT: You may not run this app on a custom ROM. It is not designed to take permissions from any app other than the Android DocumentsUI, which is provided by the system. Proper implementation of that UI is only guaranteed on vanilla vendor ROMs.

It can access other App shared storages, though. But again, this is done through the Android document UI.

Access to Termux, for example, works fine on my system. If other apps make mounting errors, that cannot be remedied here.

Android has buildt-in support for FAT and exFAT drives, so this app has as well. There is no reason to have a removable NTFS, ext4 or similar drives.
Bitlocker to go is not working either. Encryption should be file-based on removable drives.

I am German, and I personally see this Paragon software as a scam, since it doesn't and can't provide access to USB drives, because the Android operating system doesn't allow direct access to the usb port. It can only ever access existing methods.

As I said, you don't need to pay anyone 5$ for exfat access, this comes with android.

[cm-mc]

Permission is granted BY documentsui, TO Paragon. Paragon provides read and WRITE access to NTFS, etc., and it absolutely works.
My phone is a Samsung and the drive is a 8TB NTFS. I HAVE read and WRITE access to the USB drive, through either Material Files, FX, X-plore, Mixplorer, Total Commander, Documentsui, etc.
There was NO error code; it simply just didn't move any of the dozens files I selected to.