Login to your salesforce org where the package is installed.
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FIND {0} IN ALL FIELDS RETURNING Contact(Name, Id ORDER BY LASTMODIFIEDDATE DESC LIMIT 1) LIMIT 10
(Change Object Name in Query as per requirement)
Now, Go to Custom Settings and Click on Manage of “Features Entitlement“.
Mark the checkbox true for eFax.
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Provide Access to below classes.
cm_datatransfer.EFAXMessageWrapper.
cm_datatransfer.InboundFAXWebhookParser.
cm_datatransfer.InboundEFAXStatusWebhook.
cm_datatransfer.WebhookInterfaxInbound
cm_datatransfer.WebhookInterfaxOutBoundStatus
Click Save.
Remote Site Settings:
Note : Please check if there is site named eFAX and eFax Download and make sure they are Active, If not then perform following steps :
Enter Remote Site Settings in Quick Find Box.
Click on New Remote Site.
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Congratulations! You have successfully installed the Application.