2017-10-12 10:32:19,497 http-nio-8080-exec-3 ERROR [jira.emh.engine.FieldProcessorMapHandler] UnhandledException in handleCommentOrPostIssueCreationActions
java.lang.NullPointerException
	at com.atlassian.servicedesk.internal.customfields.participants.ParticipantsCFType.getStoredValues(ParticipantsCFType.java:319)
	at com.atlassian.servicedesk.internal.customfields.participants.ParticipantsCFType.validateFromParams(ParticipantsCFType.java:299)
	at com.atlassian.jira.issue.fields.ImmutableCustomField.validateParams(ImmutableCustomField.java:704)
	at com.atlassian.jira.bc.issue.DefaultIssueService.validateAndPopulateParamsWithoutScreenCheck(DefaultIssueService.java:973)
	at com.atlassian.jira.bc.issue.DefaultIssueService.validateAndPopulateParams(DefaultIssueService.java:886)
	at com.atlassian.jira.bc.issue.DefaultIssueService.validateAndUpdateIssueFromFields(DefaultIssueService.java:680)
	at com.atlassian.jira.bc.issue.DefaultIssueService.validateUpdate(DefaultIssueService.java:286)
	at sun.reflect.GeneratedMethodAccessor1202.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at com.atlassian.plugin.util.ContextClassLoaderSettingInvocationHandler.invoke(ContextClassLoaderSettingInvocationHandler.java:26)
	at com.sun.proxy.$Proxy332.validateUpdate(Unknown Source)
	at sun.reflect.GeneratedMethodAccessor1202.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at com.atlassian.plugin.osgi.bridge.external.HostComponentFactoryBean$DynamicServiceInvocationHandler.invoke(HostComponentFactoryBean.java:136)
	at com.sun.proxy.$Proxy332.validateUpdate(Unknown Source)
	at com.javahollic.jira.emh.engine.FieldProcessorMapHandler.handleCommentOrPostIssueCreationActions(FieldProcessorMapHandler.java:289)
	at com.javahollic.jira.emh.service.ProcessorRunner.runProcessor(ProcessorRunner.java:1185)
	at com.javahollic.jira.emh.service.ProcessorRunner.execute(ProcessorRunner.java:340)
	at com.javahollic.jira.emh.service.ProfileGroupRunner.runWithConfiguration(ProfileGroupRunner.java:583)
	at com.javahollic.jira.emh.service.ProfileGroupRunner.handleMessage(ProfileGroupRunner.java:127)
	at com.javahollic.jira.emh.service.EnterpriseMessageHandlerImpl.handleMessage(EnterpriseMessageHandlerImpl.java:196)
	at com.javahollic.jira.emh.ui.action.JEMHTestCases.doRun(JEMHTestCases.java:455)
	at com.javahollic.jira.emh.ui.action.JEMHTestCases.doUpdate(JEMHTestCases.java:604)

1. If possible, update Jira to version 7.3.4 and Sevice Desk to version 3.4.1
2. Verify that the exception no longer appears