hi the rule given below is compiling without error but 'then' syntax is not getting executed. when i tried to debug the rule executor class, the workingMemory.fireAllRules() is executed but when i tried to print the error message after firing, it is returning a null. DSL rule: [when]if {value1} is present in the list=exists List1(vlist1=={value1}) [then]set the error message as {value3}=err.setErrormessage({value3}); please help me out in this regard -- View this message in context: http://www.nabble.com/%22then%22-syntax-not-executing-tf3327186.html#a925... Sent from the drools - user mailing list archive at Nabble.com.