你的主机中的软件中止了一个已建立的连接。

客户端

import socket

def main():
    tcp_client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    ip = input('请输入下载服务器的ip:')
    port = int(input('请输入下载服务器的端口:'))
    tcp_client_socket.connect((ip, port))
    print("已连接至" + ip)
    while True:
        command = input('请输入命令:')
        tcp_client_socket.send(command.encode('utf-8'))
        recv_data = {}
        exec("recv_data = " + tcp_client_socket.recv(8388608).decode("utf-8"), recv_data)
        recv_data = recv_data["recv_data"]
        if recv_data["type"] == "file":
            with open(recv_data["name"], "wb") as file:
                file.write(recv_data["content"])
        elif recv_data["type"] == "code":
            if recv_data["name"] == "ok" and recv_data["content"] == "exit":
                break
            elif recv_data["name"] == 404:
                print(recv_data["content"] + "不存在!")
            elif recv_data["name"] == -1:
                print("命令" + recv_data["content"] + "错误!")
        elif recv_data["type"] == "list":
            print(recv_data["name"] + "下的文件及目录:")
            for i in recv_data["content"]:
                print(i)
    tcp_client_socket.close()

if __name__ == '__main__':
    main()

服务端

import os
import socket

def send_client(new_client_socket, client_add):
    global run
    command = new_client_socket.recv(4096).decode('utf-8')
    file_content = {"type": "", "name": "", "content": ""}
    if command == "exit":
        file_content["type"] = "code"
        file_content["name"] = "ok"
        file_content["content"] = "exit"
    elif command.split(" ")[0] == "download" and len(command.split(" ")) > 1:
        if os.path.isfile(command.split(" ")[1]):
            file_content["type"] = "file"
            file_content["name"] = command.split(" ")[1].split("\\")[-1].split("/")[-1]
            with open(command.split(" ")[1], "rb") as file:
                file_content["content"] = file.read()
            print("用户下载了{}!".format(file_content["name"]))
        else:
            file_content["type"] = "code"
            file_content["name"] = 404
            file_content["content"] = command.split(" ")[1].split("\\")[-1].split("/")[-1]
            print("用户试图下载{}!".format(file_content["name"]))
    elif command.split(" ")[0] == "dir" and len(command.split(" ")) > 1:
        if os.path.isdir(command.split(" ")[1]):
            file_content["type"] = "list"
            file_content["name"] = command.split(" ")[1]
            file_content["content"] = os.listdir(file_content["name"])
            print("用户访问了{}!".format(file_content["name"]))
        else:
            file_content["type"] = "code"
            file_content["name"] = 404
            file_content["content"] = command.split(" ")[1]
            print("用户试图访问{}!".format(file_content["name"]))
    elif command.split(" ")[0] == "dir":
        file_content["type"] = "list"
        file_content["name"] = os.getcwd()
        file_content["content"] = os.listdir(file_content["name"])
        print("用户访问了{}!".format(file_content["name"]))
    else:
        file_content["type"] = "code"
        file_content["name"] = -1
        file_content["content"] = command

    new_client_socket.send(str(file_content).encode("utf-8"))
    if command == "exit":
        exit()

def main():
    tcp_server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    tcp_server_socket.bind(('', int(input('请输入这个服务器端口:'))))
    tcp_server_socket.listen(128)
    while True:
        new_client_socket, client_add = tcp_server_socket.accept()
        print("{}已连接,端口:{}".format(*client_add))
        send_client(new_client_socket, client_add)
        new_client_socket.close()

if __name__ == '__main__':
    main()

分别运行后，客户端输入download server.py会出现以下情况：

Traceback (most recent call last):
  File "C:/Users/123/Desktop/文件/python/socket文件下载/客户端/client.py", line 32, in <module>
    main()
  File "C:/Users/123/Desktop/文件/python/socket文件下载/客户端/client.py", line 13, in main
    exec("recv_data = " + tcp_client_socket.recv(8388608).decode("utf-8"), recv_data)
ConnectionAbortedError: [WinError 10053] 你的主机中的软件中止了一个已建立的连接。

服务端给权限没有，现在是服务端拒绝链接，还有服务端口开放没？