Unable to deploy to sandbox - "Entity is not org-accessible"

Question

Trying to deploy from one Sandbox to another but I get the following error:

Here is my code:

Trigger Chat_GetOsForLiveAgent on LiveChatTranscript (before insert) {

    List<GettingOS__c> customSettings = GettingOS__c.getall().values();
    List<Case> lstcases = new List<Case>();
    System.debug('customSettings: ' + customSettings);


    for(LiveChatTranscript trans: Trigger.new) {
      if(trans.UserAgent!=null) {
        for(GettingOS__c cs: customSettings){
          if(trans.UserAgent.contains(cs.AbbrivOS__c)) {
            Case c = new Case(Id=trans.CaseId,OS__c=cs.Operating_System__c);
            lstcases.add(c);
          }
        }

      }
    }
    update lstcases;
}

Answer 1

There are some metadata components in salesforce, that are based on specific feature, like Live Agent,Sharing on specific object, Contacts to Multiple Accounts etc, and those metadata are unavailable for updates if a feature is disabled.

To ensure that all changes are properly deployed via changeset or any other deployment tool, the corresponding feature needs to be enabled in target organisation (which may be sandbox or another org).

Otherwise, next error can be shown:

entity is not org-accessible

In these scenario, Live Chat should be enabled in target sandbox before changeset deployment.