Save dialog > Open network folder results in "The network path could not be found"

Description of the Issue

Try to open a folder on a network pc in the "Save As" dialog, by pressing the button "Open" on the bottom right, results in a "The network path could not be found". But when I double click the folder itself, everything just works fine.

Steps to Reproduce the Issue

1. Open the "Save As" dialog.
2. Navigate to a network pc.
3. Click once on a shared folder.
4. Let Notepad++ open the folder by pressing the "Open" button in the bottom right corner (which usually is called "Save")

Expected Behavior

Opens the shared folder.

Actual Behavior

Dialog window greys out and after a minute or so it responds with a message box saying "The network path could not be found".

Debug Information

Notepad++ v7.5.4 (64-bit)
Build time : Jan 1 2018 - 01:50:29
Path : C:\Program Files\Notepad++\notepad++.exe
Admin mode : ON
Local Conf mode : OFF
OS : Windows 7 (64-bit)
Plugins : DSpellCheck.dll mimeTools.dll NppConverter.dll

Start by reproducing the issue in Notepad++'s Save As dialog on Windows with a network share, comparing the bottom-right Open action with double-clicking the folder. Done means selecting a shared folder and opening it succeeds without the dialog greying out or showing a network-path error.