Question:

How to disable the Email Opt In button in offline CRM?

Answer:

Email Opt In cannot be disabled on the page layout on the Account Type level.

To disable the Email Opt In button, follow the steps: 

1. Set the Approved Email Consent Mode to '1':
   Navigate to Setup --> Develop --> Custom Settings --> Approved Email Settings (Manage) --> Approved Email Consent Mode = 1
   
   
2. Be sure to activate the Approved_Email_Settings_vod__c VMobile Object Configuration (VMOC) record.
   
   
3. Clear Veeva Cache and perform a full database refresh on the mobile device.

By setting the Approved Email Consent Mode to 1, the Consent Capture feature will kick in if configured.

Related Documentation:

CRM Help Documentation: Components of Classic Consent in Approved Email