By default, a folder, list item, and library file inherits permissions from the list, library, or folder it is in. The site, list, library, or folder that site content is in is referred to as the parent. Changes to the permissions of the parent apply to all content that inherits permissions from this parent. But if you want to change the permissions at sub site or list/library level ; then first stop inheriting permission from the root site or at Library /list level. Further you can follow below steps : Click on the “Call up” menu or “…” of folder or documents that you need the unique permissions on. Click on “…” further as shown in Fig. below and then select “Shared With”. Next click on “Stop Inheriting Permissions”. Click OK on the message below: Now you can grant Permissions to this document: Do let me know if you have any additional questions.
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