i installed Jenkins application in my machine and i set the proxy correctly and whenever i was trying to install update plugins , it was showing below error. Kindly i need help for this.

{Installing Plugins/Upgrades Preparation Checking internet connectivity Checking update center connectivity Success Mailer Plugin Failure - java.io.IOException: Downloaded file D:\Program Files (x86)\Jenkins\plugins\mailer.jpi.tmp does not match expected SHA-1, expected 'P/4FkIGX5LgM5+y4xIRxN02gTHs=', actual 'YfiBQ94e9LSERsFobM5+hzkvAwM=' at hudson.model.UpdateCenter.verifyChecksums(UpdateCenter.java:1307) at hudson.model.UpdateCenter.access$900(UpdateCenter.java:124) at hudson.model.UpdateCenter$InstallationJob.replace(UpdateCenter.java:1406) at hudson.model.UpdateCenter$UpdateCenterConfiguration.install(UpdateCenter.java:846) at hudson.model.UpdateCenter$DownloadJob._run(UpdateCenter.java:1186) at hudson.model.UpdateCenter$InstallationJob._run(UpdateCenter.java:1364) at hudson.model.UpdateCenter$DownloadJob.run(UpdateCenter.java:1161) 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:110) at java.lang.Thread.run(Unknown Source)}