When I am trying to install the GitHub plugin these are the errors I am getting:

java.net.SocketTimeoutException: connect timed out
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at sun.net.NetworkClient.doConnect(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient.openServer(Unknown Source)
at sun.net.www.http.HttpClient.<init>(Unknown Source)
at sun.net.www.http.HttpClient.New(Unknown Source)
at sun.net.www.http.HttpClient.New(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.connect(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getHeaderField(Unknown Source)
at java.net.URLConnection.getHeaderFieldLong(Unknown Source)
at java.net.URLConnection.getContentLengthLong(Unknown Source)
at java.net.URLConnection.getContentLength(Unknown Source)
at hudson.model.UpdateCenter$UpdateCenterConfiguration.download(UpdateCenter.java:1125)
Caused: java.net.SocketTimeoutException: connect timed out
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.protocol.http.HttpURLConnection.getChainedException(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at hudson.model.UpdateCenter$UpdateCenterConfiguration.download(UpdateCenter.java:1141)
Caused: java.io.IOException: Failed to load http://updates.jenkins-ci.org/download/plugins/github/1.29.3/github.hpi to C:\Program Files (x86)\Jenkins\plugins\github.jpi.tmp
at hudson.model.UpdateCenter$UpdateCenterConfiguration.download(UpdateCenter.java:1148)
Caused: java.io.IOException: Failed to download from http://updates.jenkins-ci.org/download/plugins/github/1.29.3/github.hpi
at hudson.model.UpdateCenter$UpdateCenterConfiguration.download(UpdateCenter.java:1182)
at hudson.model.UpdateCenter$DownloadJob._run(UpdateCenter.java:1719)
at hudson.model.UpdateCenter$InstallationJob._run(UpdateCenter.java:1982)
at hudson.model.UpdateCenter$DownloadJob.run(UpdateCenter.java:1693)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at hudson.remoting.AtmostOneThreadExecutor$Worker.run(AtmostOneThreadExecutor.java:112)
at java.lang.Thread.run(Unknown Source)