How to Add Permissions for Client Users to Access Public Folder Content

http://technet.microsoft.com/en-us/library/aa998834.aspx

This topic explains how to use the Exchange Management Shell to add permissions for users of client programs (such as Microsoft Outlook) to access and modify public folder content. When adding these permissions, you can either use predefined permission roles (which consist of specific access rights) or you can customize permissions by manually applying the available access rights. To specify the permissions for the client user, you can use the Add-PublicFolderClientPermission cmdlet or the AddUsersToPFRecursive.ps1 user management script.

Procedure:
To use the Exchange Management Shell to specify client access rights to a public folder by using the Add-PublicFolderClientPermission cmdlet

To add Publishing Editor permissions for the user Kim to access the public folder named West Coast, run the following command:
Add-PublicFolderClientPermission -Identity “MarketingWest Coast” -AccessRights PublishingEditor -User Kim

For detailed syntax and parameter information, see Add-PublicFolderClientPermission.
To use the Exchange Management Shell to specify client access rights to a public folder by using the AddUsersToPFRecursive.ps1 management script:

To add Reviewer permissions for the user David to access the top-level public folder named Sales and all of the public folders contained within the Sales tree, run the following command:
AddUsersToPFRecursive.ps1 -TopPublicFolder “Sales” -User “David” -Permission Reviewer