Starting with version 2.3 Sync has implemented support for External SD card on Android utilizing DocumentProvider API. This made it possible for Sync to get write access to SD card on mobile devices with Android v5.0 and newer.
To save your folder on SD card, you need to disable "Simple mode" in Sync settings, so you can pick folder location 'On SD card"
Sync v 2.6. requests and needs to be granted access SD card root so as to be able to write files there. This is reuqired to be done once after fresh installation of Sync and won't be asked for after that.
The flow is the following:
1) After disabling Simple mode you'll be prompted to select location for a new share. Tap on SD card.
2) Follow the instruction in pop up. You'll be redirected to SD card provider view. Select SD card from its left side panel.
3) Be sure to select the root of SD card as this step is only for giving Sync access to the card, not for selecting share's location. Otherwise, this error will appear and will require to repeat step 2.
4) Once Sync gets access to root of SD card, you'll be redirected to select location for share.
Possible issues with access to your SD card
- You do not see the option to store folder on SD card, but instead see regular Sync's folder picker, i.e. writing to SD card is not possible!
Open "Contact Support" menu, in the E-mail field instead of your mail address type SNC.DBG.SD and hit "Send" (envelope icon), at the bottom of the screen see if your SD card is listed as available storage. If not, type SNC.DBG.SD.ENABLE and also hit "Send". Try using the SD card again.
- You still get 'No permission to write to selected folder" warning.
Make sure that you pick SD card via the above mentioned view. Do not navigate to the SD card through picking "On phone"-> level_up -> storage -> SD_card. Such method is not using the API and thus doesn't grant access to the SD card.
- You cannot create a new folder on SD card to back it up.
That's right. You can pick any existing folder as a backup folder, but creating a new one is not possible through Sync. Solution: create a folder using your file manager, and then pick it in Sync.