how do make Account Address field as mandatory field using Validation Rule?
Its not possible with standard functionality (Either PageLayout, Field Required option) so its achievable with the help of Salesforce Validation Rule:
Here is the validation rule to make the standard address fields as mandatory.
Setup –> Customize –> Accounts –> Validation Rules –> New
Error
Formula Condition for Billing Address:
OR( BillingStreet = NULL, BillingCity = NULL, BillingState = NULL, BillingPostalCode = NULL)
Error Message:
Please Enter Billing Street, Billing City, Billing State & Billing PostalCode.
Error Location:
Top of page
If you want to require the shipping address, replace from BillingStreet to ShippingStreet and so for.
Formula Condition for Shipping Address:
OR( ShippingStreet = NULL, ShippingCity = NULL, ShippingState = NULL, ShippingPostalCode = NULL)
Error Message:
Please Enter Shipping Street, Shipping City, Shipping State & Shipping PostalCode.