Thanks for your post. And mainly for the screenshots. The Transfer on background was the key!

This bug has been added to the tracker:
https://winscp.net/tracker/928

I'm sending you dev build for testing to your email address shortly.

Hi Martin,

I understand the confusion. :) I've attached two files of screenshots in an attempt to help you duplicate the issue. Further testing proved that a key piece of information was left off of the initial description. You need to change tabs for the copy to break (Steps 4 & 5 below).

WinSCP_Issue_Scenario_1_Matching_Directory.zip

This file is the situation where the Tab1 and Tab2 servers have a matching directory structure on the file system. i.e. Remote directory /var/tmp/martin_remote_server exists on both servers.

Steps to Duplicate Issue:

1. Open Server1 in Tab1 and browse to the common remote directory /var/tmp/martin_remote_server
2. Click to add a new tab, open Server2 in Tab2 and browse to the common remote directory /var/tmp/martin_remote_server
3. Drag Tab1 to be in Tab2's position
4. Click on Tab1 to select Server2
5. Click on Tab2 to select Server1
6. Copy a file via any of the three copy methods
7. File copy completed - File does not exist on the server it was copied to
8. Click on Tab1 to select Server2 - File exists here, copied to the wrong tab

WinSCP_Issue_Scenario_2_No_Matching_Directory.zip

This file is the situation where the Tab1 and Tab2 servers do not have a matching directory structure on the file system. i.e. Remote directory Server1 = /var/tmp/martin_remote_server1 exists on Server1, but not on Server2. Remote directory Server2 = /var/tmp/martin_remote_server2 exists on Server2, but not on Server1.

Steps to Duplicate Issue:

1. Open Server1 in Tab1 and browse to a unique remote directory /var/tmp/martin_remote_server1
2. Click to add a new tab, open Server2 in Tab2 and browse to a unique remote directory /var/tmp/martin_remote_server2
3. Drag Tab1 to be in Tab2's position
4. Click on Tab1 to select Server2
5. Click on Tab2 to select Server1
6. Copy a file via any of the three copy methods
7. File copy errors - See screen shot for the first error message dialog. There are two more which appear after teh first one is cleared, but I have not attached them.

Thanks. Though I'm still not sure I understand (and I definitelly cannot reproduce this yet).

I'm getting confused by this part:

It doesn't matter what directory is open on the inactive tab - the file will appear in the target directory (as listed on the copy confirmation) on the wrong server.

"target directory on the wrong server": 1) I've though that you are downloading. 2) If it is not the current directory on the inactive tab, what directory is it then?

Please try to describe it again from the scratch, step by step, giving actual paths as examples. It would help me to imagine. Screenshots would be great too! :)

Thanks for your patience with me!

I'm copying the files via drag&drop, but I've tried the other two methods with the same result. In the copy dialog I see the target directory of the server in the active tab. When I perform the copy by any of the 3 methods, the file winds up in the directory of the server that's not on the active tab. It doesn't matter what directory is open on the inactive tab - the file will appear in the target directory (as listed on the copy confirmation) on the wrong server.

Thanks for your report.
How do you copy the files? Keyboard shortcut, menu, drag&drop?
Does the Copy dialog appear? What path does it show?
https://winscp.net/eng/docs/ui_copy

Can you please register before posting?

Open an SSH session to two different servers and navigate to two different local directories. Copy a file from the remote servers to the local directories; the files are placed in the correct local directories. Now drag the first tab to place it last. The display works correctly on each tab, listing the correct local and remote server directories. Transfer the same files as above. The files are now placed in the other server session's local directory. If you rearrange the tabs back to original, the files once again transfer to the correct local directory. I also tested the reverse scenario of transferring a file from the local directory to the server directory after rearranging the tabs with the same result. The files wind up in the other server session's remote directory.

Using WinSCP 5.1.0 on Win7 Enterprise. In my instance, the filename is the same on both the local and destination servers in case that matters. This doesn't appear to be session or protocol specific, so I'm not posting a session log file as it seems irrelevant.