I Enabled audit fields , Even unable to Save my class when using LastModifiedDate and createdDate for Object "Email Message".

The Error Message is :
Error: Compile Error: Field is not writeable: EmailMessage.LastModifiedDate at line 159 column 38

Hi,

 

I have my accounts related on a way that one parent Account is pointed by its daughters with the field ParentId.

 

I need to do a trigger that when the parent account is modified in the field Recovery_actions__C(is a checkfield), this change has to go to the daughters accounts.

 

This is my trigger:

 

trigger UpdateCierrePorRecobro on Account (beforeupdate) {

 

Set<Id> addAccountsActivate = newSet<Id>();

Set<Id> addAccountsDeactivate = newSet<Id>();

 

//Aislo los id's

 

for(integer i=0;i<Trigger.new.size();i++){

//If the value has changed add to the list

if ((Trigger.new[i].Recovery_Actions__c!=Trigger.old[i].Recovery_Actions__c)) { 

if (trigger.new[i].recovery_actions__c){//changed to true

addAccountsActivate.add(Trigger.new[i].id);

}

else{//changed to false

addAccountsDeactivate.add(Trigger.new[i].id);

}

}

}

if(addAccountsActivate.size()>0){

 

//create a list of ids with the daughter ids of the main account

//????????????????????????????????????????

List<id> listaToTrue=newList<id>();

listaParaActivar.add([select id fromAccountwhereParentId in:addAccountsActivate]);

//????????????????????????????????????????????

 

Accountacc;

 

//and update the value

for(integer j=0;j<listaToTrue.size();j++){

acc.id=listaParaActivar[j];

acc.Reacovery_Actions__c=1;

updateacc;

}

}

 

}

 

 

---------------------------------------

 

I have the problem in the part where I query in order to get the ids of the daughter accounts, I dont know how to get that list of ids.

 

Anyone could help here?

 

Thanks,

Antonio