This development build should correct the problem
Download:
ffxp4.3.1.1958.zip
Unzip the flashfxp.exe into your FlashFXP program folder.
This update also includes a couple other minor fixes.
1. Fixed: Synchronized browsing between two local browsers.
2. Fixed: Connecting to a pre-existing quick connect history item now correctly moves the entry to the top of the history list.
3. Changed: The "Keyboard: Enter Key" action "execute file" in the scope of the local file browser now supports multiple selection.
4. Fixed: A lost of connection or transfer stall during a FTP upload did not apply the upload retry count, instead it immediately marked the transfer as failed.