Solved
Unexpected Error
Сервер нарушил протокол. Section=ResponseHeaderDetail=За возвратом каретки должен следовать перевод строки
Try this tip - "Error "The server committed a protocol violation. Section=ResponseHeader Detail=CR must be ......"": https://community.ptc.com/t5/PTC-Mathcad-Installation/Error-quot-The-server-committed-a-protocol-violation-Section/m-p/706423#M24
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