IncompatibleClassChangeError after ColdFusion 11 Update 5

If you use the Encrypt function in ColdFusion 11, you may experience an error that looks like this:

java.lang.IncompatibleClassChangeError: Expected static method coldfusion.runtime.CFPage.Encrypt(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String; at cfprobe2ecfm877726397._factor9(/hackmycf/probe.cfm:258) at cfprobe2ecfm877726397.runPage(/hackmycf/probe.cfm:1) at coldfusion.runtime.CfJspPage.invoke(CfJspPage.java:246) at coldfusion.tagext.lang.IncludeTag.handlePageInvoke(IncludeTag.java:736) at coldfusion.tagext.lang.IncludeTag.doStartTag(IncludeTag.java:572) at coldfusion.filter.CfincludeFilter.invoke(CfincludeFilter.java:65) at coldfusion.filter.IpFilter.invoke(IpFilter.java:45) at coldfusion.filter.ApplicationFilter.invoke(ApplicationFilter.java:466) at coldfusion.filter.RequestMonitorFilter.invoke(RequestMonitorFilter.java:42) at coldfusion.filter.MonitoringFilter.invoke(MonitoringFilter.java:40) at coldfusion.filter.PathFilter.invoke(PathFilter.java:142) at coldfusion.filter.LicenseFilter.invoke(LicenseFilter.java:30) at coldfusion.filter.ExceptionFilter.invoke(ExceptionFilter.java:94) at coldfusion.filter.ClientScopePersistenceFilter.invoke(ClientScopePersistenceFilter.java:28) at coldfusion.filter.BrowserFilter.invoke(BrowserFilter.java:38) at coldfusion.filter.NoCacheFilter.invoke(NoCacheFilter.java:58) at coldfusion.filter.GlobalsFilter.invoke(GlobalsFilter.java:38) at coldfusion.filter.DatasourceFilter.invoke(DatasourceFilter.java:22) at coldfusion.filter.CachingFilter.invoke(CachingFilter.java:62) at coldfusion.CfmServlet.service(CfmServlet.java:219) at coldfusion.bootstrap.BootstrapServlet.service(BootstrapServlet.java:89) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at coldfusion.monitor.event.MonitoringServletFilter.doFilter(MonitoringServletFilter.java:42) at coldfusion.bootstrap.BootstrapFilter.doFilter(BootstrapFilter.java:46) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at coldfusion.inspect.weinre.MobileDeviceDomInspectionFilter.doFilter(MobileDeviceDomInspectionFilter.java:121) at coldfusion.bootstrap.BootstrapFilter.doFilter(BootstrapFilter.java:46) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:422) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:744)

The solution is to clear the Template Cache, this is done quite easily in the ColdFusion administrator under Server Settings » Caching simply click the Clear Template Cache Now button, and it will work.

Another way to fix this issue is to simply edit the cfm or cfc file that contains the Encrypt call and then the CF server will automatically recompile it (due to the updated timestamp). This method would only work if Trusted Cache is not turned on.

Why did this happen? It appears to me that the internal java method signature for the Encrypt function changed, and since CF compiles your CFML into Java bytecode and then caches it, the cached java bytecode is no longer valid after the update is applied.