I use dired/tramp to view a directory on a remote machine (Linux) with pscp method, and if I do a copy (recursively) of a remote dir to either a local or another remote dir with command dired-to-copy, it fails (after entering the password) with the following message in the minibuffer:
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Tramp failed to connect. If this happens repeatedly try 'M-x tramp-cleanup-this-connection'============================================
In the "*temp*" buffer, it says:
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