In my .bash_profile I typically print out my PATH so I can see it when I login. This can cause problems when trying to use an SSH-based file transfer protocol to get files out of this machine.
Using sftp you might see something like "Received message too long 1819238756"
Using scp you will likely see nothing at all - it just won't work.
Comment out all echo statements in your profile and the problem should be resolved.
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