ContributionsMost RecentMost LikesSolutionsRe: SOAPUI won't start, Error Log says "Constraint unknown: jdk.disabled.namedCurves" Hi richie , thanks for your reply. It was indeed related to an Ubuntu upgrade: the JRE. I had used java 11.8 to run SOAPUI, because the bundled JRE 8 didn't work and wasn't replaced during upgrade. So I had copied 11.8 to SOAPUI's jre folder. See my other post . Meanwhile jre 11.8 was replaced by 11.9 in Ubuntu, which added a new property jdk.disabled.namedCurves . The property was apparently configured somewhere on my PC, but the old jre in SOAPUI was unable to understand it. So again I copied the jre (11.9) to SOAPUI, now it works. SOAPUI won't start, Error Log says "Constraint unknown: jdk.disabled.namedCurves" Trying to start SoapUI 5.6.0 on Ubuntu 18.04 with Java 11 I see only the splash screen. This version used to run on this computer; I belive some Ubuntu update caused the problem but I have no idea what to look for. The error log shows the following exception: 2021-01-06 14:42:16,344 ERROR [errorlog] java.lang.ExceptionInInitializerError java.lang.ExceptionInInitializerError at java.base/sun.security.ssl.ProtocolVersion.<init>(ProtocolVersion.java:158) at java.base/sun.security.ssl.ProtocolVersion.<clinit>(ProtocolVersion.java:41) at java.base/sun.security.ssl.SSLContextImpl$AbstractTLSContext.<clinit>(SSLContextImpl.java:560) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:315) at java.base/java.security.Provider$Service.getImplClass(Provider.java:1915) at java.base/java.security.Provider$Service.newInstance(Provider.java:1891) at java.base/sun.security.jca.GetInstance.getInstance(GetInstance.java:236) at java.base/sun.security.jca.GetInstance.getInstance(GetInstance.java:164) at java.base/javax.net.ssl.SSLContext.getInstance(SSLContext.java:168) at org.apache.http.conn.ssl.SSLContextBuilder.build(SSLContextBuilder.java:162) at org.apache.http.conn.ssl.SSLSocketFactory.<init>(SSLSocketFactory.java:289) at com.eviware.soapui.impl.wsdl.support.http.SoapUISSLSocketFactory.<init>(SoapUISSLSocketFactory.java:59) at com.eviware.soapui.impl.wsdl.support.http.HttpClientSupport$Helper.initSocketFactory(HttpClientSupport.java:309) at com.eviware.soapui.impl.wsdl.support.http.HttpClientSupport$Helper.<init>(HttpClientSupport.java:200) at com.eviware.soapui.impl.wsdl.support.http.HttpClientSupport.<clinit>(HttpClientSupport.java:70) at com.eviware.soapui.DefaultSoapUICore.initSettings(DefaultSoapUICore.java:374) at com.eviware.soapui.SwingSoapUICore.initSettings(SwingSoapUICore.java:99) at com.eviware.soapui.DefaultSoapUICore.init(DefaultSoapUICore.java:141) at com.eviware.soapui.StandaloneSoapUICore.<init>(StandaloneSoapUICore.java:38) at com.eviware.soapui.SoapUI$SoapUIRunner.run(SoapUI.java:791) at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:313) at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:770) at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721) at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715) at java.base/java.security.AccessController.doPrivileged(Native Method) at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85) at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:740) at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203) at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124) at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113) at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109) at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90) Caused by: java.lang.IllegalArgumentException: Error in security property. Constraint unknown: jdk.disabled.namedCurves at java.base/sun.security.util.DisabledAlgorithmConstraints$Constraints.<init>(DisabledAlgorithmConstraints.java:329) at java.base/sun.security.util.DisabledAlgorithmConstraints.<init>(DisabledAlgorithmConstraints.java:100) at java.base/sun.security.ssl.SSLAlgorithmConstraints.<clinit>(SSLAlgorithmConstraints.java:45) ... 34 more SolvedRe: SoapUI 5.6.0 upgrade keeps JRE 8 : java.lang.UnsupportedClassVersionError Copying a more recent JRE (Java 11) into the jre subfolder (as suggested here) fixed it. SoapUI 5.6.0 upgrade keeps JRE 8 : java.lang.UnsupportedClassVersionError When I started SoapUI 5.5.0 today, an upgrade to 5.6.0 was offered. However, after the upgrade, SoapUI doesn't start; it fails with this error: java.lang.UnsupportedClassVersionError: com/eviware/soapui/SoapUI has been compiled by a more recent version of the Java Runtime (class file version 53.0), this version of the Java Runtime only recognizes class file versions up to 52.0 I checked the jre contained within SoapUI; it is still "1.8.0_181", but obviously at least Java 9 is required. I'm on Ubuntu 18.04.4 LTS. Solved