=> ERROR [internal] load metadata for docker.io/library/ubuntu:14.04

[748811693aB]

PS C:\Users\sdzb_\Documents\BaiduSyncdisk\论文\毕业设计\代码\PointCloudSegmentation-master\PointCloudSegmentation-master> docker build -t opencv:cpp .
[+] Building 22.0s (3/3) FINISHED docker:desktop-linux
=> [internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 723B 0.0s
=> WARN: MaintainerDeprecated: Maintainer instruction is deprecated in favor of using label (line 2) 0.0s
=> ERROR [internal] load metadata for docker.io/library/ubuntu:14.04 21.9s
=> [auth] library/ubuntu:pull token for registry-1.docker.io 0.0s

[internal] load metadata for docker.io/library/ubuntu:14.04:

---

1 warning found (use docker --debug to expand):

• MaintainerDeprecated: Maintainer instruction is deprecated in favor of using label (line 2)
  Dockerfile:1

---

1 | >>> FROM ubuntu:14.04
2 | MAINTAINER Xinyuan Gui
3 |

ERROR: failed to solve: ubuntu:14.04: failed to resolve source metadata for docker.io/library/ubuntu:14.04: failed to authorize: failed to fetch oauth token: Post "https://auth.docker.io/token": dial tcp 31.13.75.12:443: connectex: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.