Adding folder in SD card to EXTERNAL FILES section will fail and show error

[kerhbal]

trafficstars

I there, I want to modify some files in SD card in place, so I tried to add a folder to EXTERNAL FILES section, but I see this behaviour:

• it first goes to a blank page with title of folder name, looks like to treat it as a file to open
• then the error is "The file my_some_folder could not be loaded".

can someone show me how to do it if it's possible? thanks