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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I am Sakthivel Madesh, a certified Salesforce Advanced Developer & Administrator working on Salesforce Technology since 2011. I am currently working in Techforce Services as Sr. Salesforce Developer. I have worked on multiple technologies Like PHP, Java, Salesforce, I am very passionate about Salesforce and to earn 15x Salesforce Certification. I love Trailhead for learning Salesforce Skill and Become a Trailhead 5x Ranger too. I Love to Learn & Share my Salesforce knowledge to Salesforce Learners/Beginner using My Blog and Salesforce Community.