# Filename: Add_Perms.ps1
# Version: 2014.06.03; Jay Carper, https://exchangetips.us
# Purpose: Adds permissions to all folders in a mailbox for the 
# given user name.
#
# Example:
# add_perms SharedMailbox UserName
#
# Requires Exchange Management Shell
#
# Return an error if no mailbox or user name was entered.

Param(
    [string]$Identity = `
        $(throw `
        "No value entered for the shared mailbox identity."),
    [String]$User = `
        $(throw "No value entered for the user identity.")
)

# Run if the mailbox name is valid.
if (Get-Mailbox $Identity -ea SilentlyContinue) {

    # Run if the username is valid.
    if (Get-Mailbox $User -ea SilentlyContinue) {
        Write-Host " "
        Write-Host "Errors are normal on folders where $User" `
            -ForegroundColor Yellow
        Write-Host "already has permissions." `
            -ForegroundColor Yellow

        # Add permissions on the mailbox root.
        $Root = $Identity+":\"
        Add-MailboxFolderPermission $Root -User $User `
            -AccessRights PublishingEditor

        # Add permissions to all other applicable mailbox folders. 
        # Skips folders that usually cause errors or that don't 
        # matter.
        $MBFolders = (Get-MailboxFolderStatistics $Identity | `
            ?{($_.FolderPath -ne "/Top of Information Store") `
            -and ($_.FolderPath -ne "/Recoverable Items") -and `
            ($_.FolderPath -ne "/Deletions") -and ($_.FolderPath `
            -ne "/Purges") -and ($_.FolderPath -ne "/Versions")})

        ForEach($Path in $MBFolders) {
            $Folder = $Identity + ":" + `
                $Path.FolderPath.Replace("/","\")
            Add-MailboxFolderPermission $Folder -User $User `
                -AccessRights PublishingEditor
        }

        Write-Host `
            "Added permissions for $User on mailbox $Identity." `
            -ForegroundColor Yellow
        Write-Host " "
        Write-Host `
            "You may see errors if $User already had perms." `
            -ForegroundColor Yellow
        Write-Host "Those errors are safe to ignore." `
            -ForegroundColor Yellow
    }

    # Display an error if the username is not valid.
    else {
        Write-Host "Username $User not found." `
            -ForegroundColor Red
    }
}

# Display an error if the mailbox is not valid.
else {Write-Host "Mailbox $Identity not found." -ForegroundColor Red}