file upload via FTP has 0kb size

Very strange issue: all uploaded fies has 0 kb size, restart pure-ftpd service, even restart server couldn't solve probem.

Check FileZilla log: only did it after spending two hours of debugging, searching, googling...
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Response:    150 Accepted data connection
Response:    226-Error during read from data connection
Response:    226 Transfer aborted
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Ok. Restart Router -> Problem still there!
Next step. Restart Computer -> it fixed issue

Summary: "The fact is natural simple, however some people (including me) make it more difficult, then blame for bad luck."