In the line below, there's a ":" after lst_opencase. Should be an "=".
List<Id> lst_opencase : [SELECT c.OwnerId FROM Case c where c.RecordTypeId = '012300000001mEJAAY'and c.Status !='Closed' and c.Enhancement_Roadmap_Date__c < :dt];
lst_opencase is a list of Case objects, and Case.ownerid is the schema information for the ownerId field on Case, so list_opencase.add(Case.ownerid) doesn't make any sense.
Date dt = System.Date.today(); List<Case> lst_opencase = [SELECT c.OwnerId FROM Case c where c.RecordTypeId = '012300000001mEJAAY' and c.Status ='Closed' and c.Enhancement_Roadmap_Date__c < :dt];
string[] arryOfIds = new string[lst_opencase.size()];
In the line below, there's a ":" after lst_opencase. Should be an "=".
List<Id> lst_opencase : [SELECT c.OwnerId FROM Case c where c.RecordTypeId = '012300000001mEJAAY'and c.Status !='Closed' and c.Enhancement_Roadmap_Date__c < :dt];
lst_opencase is a list of Case objects, and Case.ownerid is the schema information for the ownerId field on Case, so list_opencase.add(Case.ownerid) doesn't make any sense.
Date dt = System.Date.today();
List<Case> lst_opencase = [SELECT c.OwnerId FROM Case c where c.RecordTypeId = '012300000001mEJAAY' and c.Status ='Closed' and c.Enhancement_Roadmap_Date__c < :dt];
string[] arryOfIds = new string[lst_opencase.size()];
for(Integer I = 0; i < lst_opencase.size(); i++)
{ arryOfIds.add(lst_opencase[i].Id)}
Messaging.MassEmailMessage mEmail = new messaging.MassEmailMessage();
mEmail.setTargetObjectIds(arrayOfIds);
mEmail.setReplyTo('test@test.com');
mEmail.setSaveAsActivity(false);
mEmail.setTemplateId('00X300000017Ybx');
Messaging.sendEmail(new Messaging.MassEmailMessage[] { mEmail });
thanks sforce...the code will not work though since you can only send emails to leads,contacts or users..I was able to figure it out