Thanks for the additional replies!

There is a slight development.

The problem was coming forward in this case because I was transferring a bunch of files to a newly acquired USB drive.

I was getting a collection of errors including the regular duplicate file problem.

I reformatted the drive to NTFS. I think the drive came with an older format for wider compatibility. After reformatting, most of the errors went away. The duplicate file problem did too.

So this is some sort of naming thing to do with the different file systems.

Not to do with your file transfer program (which I love by the way). I wasn't convinced the problem was in your software but I came here in case you had seen my complaint before...

Please attach a full log file showing the problem.

Thanks for the note!

That's one of the things I thought of and it accounts for some of them.

But I get the same issue when transferring from my Windows computer to a Web server as well. Also there are many cases where I can't find the mixed case duplicates. Sometimes I think the software is transferring the same file more than once. But I'm not sure. Sometimes I think there may be more than one path leading to the same file so the software sees it as two files. But if there were to routes to the same folder it would get a duplicate warning for every file in the folder...

So I'm looking for other things to check for.

You possibly have two files on remote folder with the very same name except for a case. Your server may have case-sensitive files systems. Windows does not. So when downloading "file.txt", followed by "File.txt", the first one gets overwritten.

When I transfer a large folder to my computer or to a Web server, I often get a message that it is trying to over write a duplicate file.

This puzzles me since I don't expect this when transferring a whole folder for the first time.

Any ideas what to do?

I've not convinced myself this is a bug as it could be some sort of user error or something outside the ftp program.