2020-12-02 12:10:05.579+0000 [id=476] WARNING h.i.i.InstallUncaughtExceptionHandler#handleException: Caught unhandled exception with ID c6dd3bd7-4b34-449e-ace0-9005419d1a2c
org.kohsuke.stapler.WrongTypeException: Got type array but no lister class found for type class java.lang.String
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:724)
at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:478)
at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:787)
Caused: java.lang.IllegalArgumentException: Failed to convert the instanceCapStr parameter of the constructor public hudson.plugins.ec2.AmazonEC2Cloud(java.lang.String,boolean,java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.util.List,java.lang.String,java.lang.String)
at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:789)
at org.kohsuke.stapler.RequestImpl.access$200(RequestImpl.java:83)
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:678)
Caused: java.lang.IllegalArgumentException: Failed to instantiate class hudson.plugins.ec2.AmazonEC2Cloud from {"cloudName":"aws demo jenkins","includeUser":["false","false"],"credentialsId":"demo-jenkins-aws","useInstanceProfileForCredentials":false,"altEC2Endpoint":"","region":"eu-west-1","sshKeysCredentialsId":"demo-jenkins-aws-sshkey","instanceCapStr":["",""],"noDelayProvisioning":false,"roleArn":"","roleSessionName":"","minimumNumberOfInstances":"","minimumNumberOfSpareInstances":"","iamInstanceProfile":"","deleteRootOnTermination":false,"useEphemeralDevices":false,"customDeviceMapping":"","launchTimeoutStr":"","associatePublicIp":false,"connectionStrategy":"PRIVATE_IP","connectBySSHProcess":false,"hostKeyVerificationStrategy":"CHECK_NEW_HARD","maxTotalUses":"-1","nodeProperties":{"stapler-class-bag":"true","org-jenkinsci-plugins-matrixauth-AuthorizationMatrixNodeProperty":false,"":"0","inheritanceStrategy":{"stapler-class<span class="code-quote">":["org.jenkinsci.plugins.matrixauth.inheritance.InheritGlobalStrategy","org.jenkinsci.plugins.matrixauth.inheritance.NonInheritingStrategy"],"$class<span class="code-quote">":["org.jenkinsci.plugins.matrixauth.inheritance.InheritGlobalStrategy","org.jenkinsci.plugins.matrixauth.inheritance.NonInheritingStrategy"]},"data":{"anonymous":{"hudson.model.Computer.Build":false,"hudson.model.Computer.Configure":false,"hudson.model.Computer.Connect":false,"hudson.model.Computer.Delete":false,"hudson.model.Computer.Disconnect":false},"authenticated":{"hudson.model.Computer.Build":false,"hudson.model.Computer.Configure":false,"hudson.model.Computer.Connect":false,"hudson.model.Computer.Delete":false,"hudson.model.Computer.Disconnect":false},"__unused__":{"hudson.model.Computer.Build":false,"hudson.model.Computer.Configure":false,"hudson.model.Computer.Connect":false,"hudson.model.Computer.Delete":false,"hudson.model.Computer.Disconnect":false}}},"stapler-class<span class="code-quote">":"hudson.plugins.ec2.AmazonEC2Cloud","$class<span class="code-quote">":"hudson.plugins.ec2.AmazonEC2Cloud"}
at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:681)
at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:478)
at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:474)
at hudson.model.Descriptor.newInstance(Descriptor.java:598)
vpernankil are you using the 1.54 version of the plugin?