Need to Access Managed Package Objects and fields in Apex trigger
<p>i have to write an apex trigger on a Managed Packaged insttalled object and access in field for new and old values inside Apex trigger.</p>

<p>Please see below the piece of code that i am using in here:</p>

<pre><code>trigger EmailScoreCalculator on sendgrid4sf__SendGrid_Email_Status__c (after        update ) {

 sendgrid4sf__SendGrid_Email_Status__c  oldOpp = Trigger.oldMap.get(sendgrid4sf__SendGrid_Email_Status__c.Id);
</code></pre>

<p>Object Name : sendgrid4sf__SendGrid_Email_Status__c(Object installed from Manage Package)</p>

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    <p>But i am getting invalid Key In Map Error:</p>
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<p>Please Suggest is it because of Manage-package object or anything Wrong i am doing here,thanks.</p>

<p>Note: I am not able to see object "sendgrid4sf__SendGrid_Email_Status__c" in workbench.</p>