Jenkins git hub issue

Dear Team,

Once i provide git url, i get below mentioned message. How to resolve it. Please help

An internal error occurred during form field validation (HTTP 500). Please reload the page and if the problem persists, ask the administrator for help.

Thanks and regards

Hi there,

“it doesn’t work” is always hard to remote debug. Try to always include these 3 things.

  1. what did you try? (Code samples, command lines, screenshots, videos, etc)
  2. what happened? (Error messages, description, outputs, stuff)
  3. what did you expect to happen?

Otherwise, it’s hard for us to get into your context and you’ll have to have someone who is exactly knowledgeable come along.

Others need enough information in order to duplicate the problem that you are seeing. Others won’t be able to duplicate the problem based on your description.

When I enter a git URL into Jenkins pages (job definition, system configuration, Pipeline syntax snippet generator, etc.) it responds as I expect. That works whether I’m running Jenkins behind an NGINX reverse proxy or accessing it directly. It works with the current versions of plugins that I’m using.

Dear all,

Thanks for your reply,

I am trying to follow the exact steps of below mentioned URL Link,

URL Link : Continuous Deployment of .NET Projects using Jenkins | Muktak Joshi

But while implementing the GitHub repository URL, It replies with below message:

Message : An internal error occurred during form field validation (HTTP 500). Please reload the page and if the problem persists, ask the administrator for help.

Once i save and try to build the stuff with only GitHub repository URL and with private key credential,
i see Failure message in my console log output.

Console Log output is as follows :

FATAL: Cannot invoke “String.equals(Object)” because the return value of “org.kohsuke.putty.PuTTYKey.getAlgorithm()” is null
java.lang.NullPointerException: Cannot invoke “String.equals(Object)” because the return value of “org.kohsuke.putty.PuTTYKey.getAlgorithm()” is null
at org.kohsuke.putty.PuTTYKey.toOpenSSH(
at com.cloudbees.jenkins.plugins.sshcredentials.impl.BasicSSHUserPrivateKey.getPrivateKeys(
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.createSshKeyFile(
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandWithCredentials(
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$1.execute(
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$2.execute(
at hudson.plugins.git.GitSCM.retrieveChanges(
at hudson.plugins.git.GitSCM.checkout(
at hudson.scm.SCM.checkout(
at hudson.model.AbstractProject.checkout(
at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(
at jenkins.scm.SCMCheckoutStrategy.checkout(
at hudson.model.AbstractBuild$
at hudson.model.Run.execute(
at hudson.model.ResourceController.execute(
Finished: FAILURE

If i open the configure tab once again i see below screen,

Please help.

thanks and regards

That is a 4 year old blog post. You may want to ask the author if they have an update to the blog post to make it current.

That might indicate that you entered a private key without including the algorithm portion of the private key. An SSH private key specifies its algorithm.

For example, when I created an ED25519 private key, the result private key file was:


The public key of that private key was:

ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIMgrnZOa4WakHi2j3EOKVxVtz9HySUcoCVNtvs7l1UdK

If you enter the wrong value in the private key credential, use of that credential might report the type of error that you are seeing.

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