Using WinSCP 4.3.7 on Windows 7, connecting over straight FTP to a Windows 2008 server. Synchronize always fails when the directories are very out of sync. For example, perhaps more than X files exist remotely but not locally. I don't know what X is exactly, but I know it's more than 15. If it's a small number of differences, the error does not occur.
The file sizes range from 200KB up to 3MB, and the size of the directory is currently around 5,500 items, although I experienced the error as early as 4,500 items.
I use the synchronize function in a backup script like this:
option batch on
option confirm off
open "user@host"
cd Backups\Diffs
lcd Diffs
synchronize local
exit
Edit: to be more specific, the error is this:
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Error
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Timeout waiting for external console to complete the command.
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OK Help
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