Edit: I just saw that you prefer debug reports via e-mail. I sent you the result that way.

Thanks for your report.
I have sent you an email with a debug version of WinSCP to the address you have used to register on this forum.

I'm using the portable version of WinSCP 5.15.9 thru a freshly installed Wine 5.0.0-bioniq from the official WineHQ repo on Linux Mint 18.04 LTS.
Steps to reproduce:
1. Connect to a remote SFTP server.
2. Create a test folder and a file like test.txt on the remote server with WinSCP.
3. Drag and drop the test file into the folder.
4. Exception happens.

This happens with everything that's drag & dropped into a folder.
The moving process works successfully though.

Let me know in case this is Wine related and I'll happily report it there.

WinSCP 5.15.9

Error message:
External exception 80000101

Stack trace:
(F7F70B59)WinSCP.exe
(00081D0E)ntdll.dll
(000843AA)ntdll.dll
(0008454B)ntdll.dll

followed by

Stack trace:
(000099AE)
(0092812A)
(0092A192)
(00926F4C)
(00081D0E)ntdll.dll
(000843AA)ntdll.dll
(0008454B)ntdll.dll
(00009C5A)
(000AD16E)
(0071740A)
(0081E9FF)
(0081E975)
(0081EB1E)
(00822C5B)
(0001675C)
(00010607)
(00010720)
(00021C87)
(0002298B)
(00023FA9)
(00445B9E)
(00479652)

(00928795)
(00929D6F)
(00817C2C)
(0071740A)
(0081E9FF)
(0081E975)
(0081EB1E)
(00822C5B)
(0001675C)
(00010607)
(00010720)
(00021C87)
(0002298B)
(00023FA9)
(00445B9E)
(00479652)

(00928795)
(00929D6F)
(00717179)
(0081E9FF)
(0081E975)
(0081EB1E)
(00822C5B)
(0001675C)
(00010607)
(00010720)
(00021C87)
(0002298B)
(00023FA9)
(00445B9E)
(00479652)

(00928795)
(00929D6F)
(0081EE41)
(00822C5B)
(0001675C)
(00010607)
(00010720)
(00021C87)
(0002298B)
(00023FA9)
(00445B9E)
(00479652)

(00928795)
(00929D6F)
(00016830)
(00010607)
(00010720)
(00021C87)
(0002298B)
(00023FA9)
(00445B9E)
(00479652)


Status: all_insignificant

I know how to reproduce the problem or the problem happens frequently enough. I wish to be contacted by the WinSCP team to help resolving the problem.