Files are placed with 0 bytes. Server unexpectedly closed network connection.

Installed WinSCP without changing any of the default settings.

SFTP to remote server works fine both with password and RSA key and passphrase.
I'm able to navigate through folders, delete files, and make modifications to file properties.

The problem is that I can't place local files onto the server with drag and drop.
Permissions: Username is the owner of all folders and files.
On my older computer using older version of WinSCP and the same login information everything works fine.

Specific errors during upload attempt:
1. Server unexpectedly closed network connection.
2. Copying files to remote side failed.

I can try to reconnect, but it just loops continuously.

I suspect it's my Windows 10 stopping the connection? I've tried to allow through firewall. No luck.

I've run out things to try and am looking for help.
Thanks!

. 2019-01-07 21:06:59.111 Copying 1 files/directories to remote directory "/home/[…]/folder" - total size: 1,582
. 2019-01-07 21:06:59.111 PrTime: Yes; PrRO: No; Rght: rw-r--r--; PrR: No (No); FnCs: N; RIC: 0100; Resume: S (102400); CalcS: Yes; Mask: *.*
. 2019-01-07 21:06:59.111 TM: B; ClAr: No; RemEOF: No; RemBOM: No; CPS: 0; NewerOnly: No; InclM: ; ResumeL: 0
. 2019-01-07 21:06:59.111 AscM: *.*html; *.htm; *.txt; *.php; *.php3; *.cgi; *.c; *.cpp; *.h; *.pas; *.bas; *.tex; *.pl; *.js; .htaccess; *.xtml; *.css; *.cfg; *.ini; *.sh; *.xml
. 2019-01-07 21:06:59.111 Getting real path for '/home/[…]/folder'
> 2019-01-07 21:06:59.111 Type: SSH_FXP_REALPATH, Size: 71, Number: 33296
< 2019-01-07 21:06:59.111 Type: SSH_FXP_STATUS, Size: 24, Number: 33028
. 2019-01-07 21:06:59.111 Discarding reserved response
< 2019-01-07 21:06:59.150 Type: SSH_FXP_NAME, Size: 143, Number: 33296
. 2019-01-07 21:06:59.150 Real path is '/home/[…]/folder'
. 2019-01-07 21:06:59.155 File: 'C:\Users\[…]base.html' [2018-12-04T06:41:07.000Z] [1582]
. 2019-01-07 21:06:59.155 Copying "C:\Users\[…]base.html" to remote directory started.
. 2019-01-07 21:06:59.157 Binary transfer mode selected.
. 2019-01-07 21:06:59.157 Opening remote file.
> 2019-01-07 21:06:59.157 Type: SSH_FXP_OPEN, Size: 96, Number: 33539
< 2019-01-07 21:06:59.190 Type: SSH_FXP_HANDLE, Size: 13, Number: 33539
> 2019-01-07 21:06:59.190 Type: SSH_FXP_WRITE, Size: 1607, Number: 34054
> 2019-01-07 21:06:59.191 Type: SSH_FXP_CLOSE, Size: 13, Number: 34308
> 2019-01-07 21:06:59.191 Type: SSH_FXP_SETSTAT, Size: 92, Number: 33801
. 2019-01-07 21:06:59.234 Server unexpectedly closed network connection
. 2019-01-07 21:06:59.234 Connection was lost, asking what to do.
. 2019-01-07 21:06:59.234 Asking user:
. 2019-01-07 21:06:59.234 Server unexpectedly closed network connection. ()
* 2019-01-07 21:07:01.220 (ESshFatal) Server unexpectedly closed network connection.
* 2019-01-07 21:07:01.220 Copying files to remote side failed.

. 2019-01-07 21:06:43.466 [Background 1] Unknown server extension posix-rename@openssh.com="1"
. 2019-01-07 21:06:43.466 [Background 1] Supports statvfs@openssh.com extension version "2"
. 2019-01-07 21:06:43.466 [Background 1] Unknown server extension fstatvfs@openssh.com="2"
. 2019-01-07 21:06:43.466 [Background 1] Supports hardlink@openssh.com extension version "1"
. 2019-01-07 21:06:43.466 [Background 1] Unknown server extension fsync@openssh.com="1"
. 2019-01-07 21:06:43.466 [Background 1] We believe the server has signed timestamps bug
. 2019-01-07 21:06:43.466 [Background 1] 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
. 2019-01-07 21:06:43.466 [Background 1] Limiting packet size to OpenSSH sftp-server limit of 262148 bytes

What do you mean by "another CPU"?

martin wrote:

What do you mean by "another CPU"?

I mean that I have my old computer with WinSCP on it and with that computer and that WinSCP I log in with the same username and log in information and have no problem placing local files to the remote server.

Can you post complete session log files from both machines?

martin wrote:

Can you post complete session log files from both machines?

Martin, where does that live? I know how to access the logs from the programs, which I've pasted above, but I'm not sure what you mean by "complete session log files." Also it's not just "both" machines. There are three others who are able to transfer files locally to our remote server. It's just the one Windows 10 computer that cannot.

Thanks!

Martin and anyone else reading this,

The solution was to uninstall this program:
https://www.advanceduninstaller.com/Killer-Ethernet-Performance-Suite-b4e8ba0e168599a5644a02bf81aae6aa-application.htm

It was installed out of the box on the new machine alongside another application, Killer Wireless Driver UWD. The two programs were conflicting with one another when I would try to place local files to a remote server. I don't know anymore details than that.

Thanks for sharing your solution.