How to add a custom field in an Attachment Object?

Salesforce Attachment and Notes object are not customizable so that we can’t create a custom field in Attachment and Notes Object.

View Account/Case/ Custom Pa page layout then you will see “the list is not customizable.” for notes and attachement.

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2x Salesforce MVP | Platform Champion | 18x Salesforce Certified | MuleSoft Certified | 8x Trailhead Ranger | TechForce Services | Sydney | Australia