SOLVED: I discovered that in setting up the CoreFTP server path, I had used a forward slash instead of back slash. It's working fine now.

To test WinSCP, I wanted to start with two machines on the same network behind the same router.

I created an SFTP server using CoreFTP on a Windows XP machine behind my DDWRT router at 192.168.1.15. I'm using WinSCP with Windows 8.1 on 192.168.1.6. Router has port 22 forwarded to both 192.168.1.15 and 192.168.1.6. I made the root directory for the server on the XP machine C:\CoreFTP and shared that folder.

When I try to log on, it yields the following messages:

Authenticated
Starting the session...
Reading the remote directory...

THEN

Error listing directory "/".
Permission denied.
Error code: 3
Error message from server: Permission denied

What am I doing wrong?

Here's the log:

. 2016-10-30 18:44:06.560

--------------------------------------------------------------------------
. 2016-10-30 18:44:06.560 WinSCP Version 5.9.2 (Build 6958) (OS 6.3.9600 - Windows 8.1)
. 2016-10-30 18:44:06.560 Configuration: HKCU\Software\Martin Prikryl\WinSCP 2\
. 2016-10-30 18:44:06.560 Log level: Normal
. 2016-10-30 18:44:06.560 Local account: MyHomeComputer\Tom
. 2016-10-30 18:44:06.560 Working directory: C:\Program Files (x86)\WinSCP
. 2016-10-30 18:44:06.560 Process ID: 5572
. 2016-10-30 18:44:06.561 Command-line: "C:\Program Files (x86)\WinSCP\WinSCP.exe"
. 2016-10-30 18:44:06.561 Time zone: Current: GMT-5, Standard: GMT-6 (Central Standard

Time), DST: GMT-5 (Central Daylight Time), DST Start: 3/13/2016, DST End: 11/6/2016
. 2016-10-30 18:44:06.561 Login time: Sunday, October 30, 2016 6:44:06 PM
. 2016-10-30 18:44:06.561

--------------------------------------------------------------------------
. 2016-10-30 18:44:06.561 Session name: tom@192.168.1.15 (Site)
. 2016-10-30 18:44:06.561 Host name: 192.168.1.15 (Port: 22)
. 2016-10-30 18:44:06.561 User name: tom (Password: Yes, Key file: No)
. 2016-10-30 18:44:06.561 Tunnel: No
. 2016-10-30 18:44:06.561 Transfer Protocol: SFTP (SCP)
. 2016-10-30 18:44:06.561 Ping type: Off, Ping interval: 30 sec; Timeout: 15 sec
. 2016-10-30 18:44:06.561 Disable Nagle: No
. 2016-10-30 18:44:06.561 Proxy: None
. 2016-10-30 18:44:06.561 Send buffer: 262144
. 2016-10-30 18:44:06.561 SSH protocol version: 2; Compression: No
. 2016-10-30 18:44:06.561 Bypass authentication: No
. 2016-10-30 18:44:06.561 Try agent: Yes; Agent forwarding: No; TIS/CryptoCard: No; KI:

Yes; GSSAPI: No
. 2016-10-30 18:44:06.561 Ciphers: aes,chacha20,blowfish,3des,WARN,arcfour,des; Ssh2DES:

No
. 2016-10-30 18:44:06.561 KEX: ecdh,dh-gex-sha1,dh-group14-sha1,rsa,WARN,dh-group1-sha1
. 2016-10-30 18:44:06.561 SSH Bugs:

Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto
. 2016-10-30 18:44:06.561 Simple channel: Yes
. 2016-10-30 18:44:06.561 Return code variable: Autodetect; Lookup user groups: Auto
. 2016-10-30 18:44:06.561 Shell: default
. 2016-10-30 18:44:06.561 EOL: LF, UTF: Auto
. 2016-10-30 18:44:06.561 Clear aliases: Yes, Unset nat.vars: Yes, Resolve symlinks: Yes;

Follow directory symlinks: No
. 2016-10-30 18:44:06.561 LS: ls -la, Ign LS warn: Yes, Scp1 Comp: No
. 2016-10-30 18:44:06.561 SFTP Bugs: Auto,Auto
. 2016-10-30 18:44:06.561 SFTP Server: default
. 2016-10-30 18:44:06.561 Local directory: C:\Users\Tom\Documents, Remote directory: /,

Update: Yes, Cache: Yes
. 2016-10-30 18:44:06.561 Cache directory changes: Yes, Permanent: Yes
. 2016-10-30 18:44:06.561 Recycle bin: Delete to: No, Overwritten to: No, Bin path:
. 2016-10-30 18:44:06.561 DST mode: Unix
. 2016-10-30 18:44:06.561

--------------------------------------------------------------------------
. 2016-10-30 18:44:06.801 Looking up host "192.168.1.15" for SSH connection
. 2016-10-30 18:44:06.801 Connecting to 192.168.1.15 port 22
. 2016-10-30 18:44:06.803 We claim version: SSH-2.0-WinSCP_release_5.9.2
. 2016-10-30 18:44:06.854 Server version: SSH-2.0-CoreFTP-0.3.3
. 2016-10-30 18:44:06.854 We believe remote version has SSH-2 channel request bug
. 2016-10-30 18:44:06.854 Using SSH protocol version 2
. 2016-10-30 18:44:06.854 Have a known host key of type rsa2
. 2016-10-30 18:44:06.854 Doing Diffie-Hellman group exchange
. 2016-10-30 18:44:07.055 Doing Diffie-Hellman key exchange with hash SHA-256
. 2016-10-30 18:44:07.208 Host key fingerprint is:
. 2016-10-30 18:44:07.208 ssh-rsa 2048 3d:b9:97:0d:73:f9:3a:27:73:be:3c:1e:06:b0:82:27
. 2016-10-30 18:44:07.208 Verifying host key rsa2 0x23,0xb6a9cfd418a86fa7

3d314b29521f1394 f295036c0acaafef 8ba5760265b56c98 832bae35ae6e024a df68b5f26053214f

5b8e9f35f04e15a6 efe4d8b2b98cc381 a29e96e96948dd3b 0f4dc771a67f5950 2f895870dc091e20

b994968f8bce175c 21514193688eed1d d7f30590e1926897 98d7ddedddeb183e fc07eea53c4911f4

9212a24189ba43b4 478acc0a872674ab 0c3017d7a88bb35d c3095a18562a6fdd 5fd3d6e60fc1173f

c2d6ba0a2ef8085c 99515b3c98549599 411ffda324a5ff60 5d14ba972da73e5b c911ab0992871779

191358b4eec4a1a1 30f003b76a8c8e1f f2cef6b7b055f70f 3a721fb8d4062b02 1bd981e1df7e3fe5

3640aa63474ba83d with fingerprint ssh-rsa 2048

3d:b9:97:0d:73:f9:3a:27:73:be:3c:1e:06:b0:82:27
. 2016-10-30 18:44:07.261 Host key matches cached key
. 2016-10-30 18:44:07.262 Initialised AES-256 SDCTR client->server encryption
. 2016-10-30 18:44:07.262 Initialised HMAC-SHA-256 client->server MAC algorithm
. 2016-10-30 18:44:07.263 Initialised AES-256 SDCTR server->client encryption
. 2016-10-30 18:44:07.263 Initialised HMAC-SHA-256 server->client MAC algorithm
! 2016-10-30 18:44:07.264 Using username "tom".
. 2016-10-30 18:44:07.317 Server offered these authentication methods: password
. 2016-10-30 18:44:07.317 Prompt (password, "SSH password", <no instructions>,

"&Password: ")
. 2016-10-30 18:44:07.317 Using stored password.
. 2016-10-30 18:44:07.370 Sent password
. 2016-10-30 18:44:07.372 Access granted
. 2016-10-30 18:44:07.372 Opening session as main channel
. 2016-10-30 18:44:07.373 Opened main channel
. 2016-10-30 18:44:07.558 Started a shell/command
. 2016-10-30 18:44:07.577

--------------------------------------------------------------------------
. 2016-10-30 18:44:07.577 Using SFTP protocol.
. 2016-10-30 18:44:07.577 Doing startup conversation with host.
> 2016-10-30 18:44:07.632 Type: SSH_FXP_INIT, Size: 5, Number: -1
< 2016-10-30 18:44:07.633 Type: SSH_FXP_VERSION, Size: 5, Number: -1
. 2016-10-30 18:44:07.633 SFTP version 3 negotiated.
. 2016-10-30 18:44:07.633 We believe the server has signed timestamps bug
. 2016-10-30 18:44:07.633 We will use UTF-8 strings until server sends an invalid UTF-8

string as with SFTP version 3 and older UTF-8 strings are not mandatory
. 2016-10-30 18:44:07.633 Changing directory to "/".
. 2016-10-30 18:44:07.633 Getting real path for '/'
> 2016-10-30 18:44:07.633 Type: SSH_FXP_REALPATH, Size: 10, Number: 16
< 2016-10-30 18:44:07.634 Type: SSH_FXP_NAME, Size: 23, Number: 16
. 2016-10-30 18:44:07.634 Real path is '/'
. 2016-10-30 18:44:07.634 Trying to open directory "/".
> 2016-10-30 18:44:07.634 Type: SSH_FXP_LSTAT, Size: 10, Number: 263
< 2016-10-30 18:44:07.635 Type: SSH_FXP_ATTRS, Size: 37, Number: 263
. 2016-10-30 18:44:07.635 Getting current directory name.
. 2016-10-30 18:44:07.834 Listing directory "/".
> 2016-10-30 18:44:07.834 Type: SSH_FXP_OPENDIR, Size: 10, Number: 523
< 2016-10-30 18:44:07.835 Type: SSH_FXP_STATUS, Size: 34, Number: 523
< 2016-10-30 18:44:07.835 Status code: 3, Message: 523, Server: Permission denied,

Language:
* 2016-10-30 18:44:07.935 (ECommand) Error listing directory '/'.
* 2016-10-30 18:44:07.935 Permission denied.
* 2016-10-30 18:44:07.935 Error code: 3
* 2016-10-30 18:44:07.935 Error message from server: Permission denied
. 2016-10-30 18:44:09.044 Startup conversation with host finished.
. 2016-10-30 18:44:15.561 Closing connection.
. 2016-10-30 18:44:15.561 Sending special code: 12
. 2016-10-30 18:44:15.561 Sent EOF message