Hello.

I'm having an odd issue with test code for a trigger.  In short, I want to insert an Opportunity, then update that same Opportunity with one changed field.  Snippet of code is below...

        Account acct1 = new Account(Name = 'opptriggertestacctname');
        insert acct1;
       
        Opportunity opp1 = new Opportunity(Name = 'opptriggertest_oppname1'
                                            , AccountId = acct1.Id
                                            , StageName = 'stage1'
                                            , CloseDate = Date.today()
                                            , Type_Of_Sale__c = 'Exclusive'
                                            , Authorized_Initials__c = 'cm');
        insert opp1 ;

         Opportunity retOpp = [SELECT Id
             FROM Opportunity WHERE Id = :opp1.Id LIMIT 1];
         
         retOpp.StageName = 'Closed Won';
         update retOpp;        

Error: DmlException: Update failed: First exception on row 0 with id 006...; first error: FIELD_CUSTOM_VALIDATION_EXCEPTION, Business ID for ... is missing or invalid.

Gives me a line number - it's the line where i'm attempting to do the update.

I don't have any validation rule that matches that message.  What is Business ID?  One additional note: if I remove the retOpp.StageName = 'Closed Won'; line - and just do the update, it doesn't fail.  (But then it doesn't provide any coverage...)

Any help is greatly appreciated.  I've never had this issue before...

Thanks

Chris