Automatic download of Internet Calendar appointment attachments must be disallowed.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-228469	SRG-APP-000209	DTOO284	SV-228469r508021_rule	2022-03-11	2

Description
This policy setting controls whether Outlook downloads files attached to Internet Calendar appointments. If you enable this policy setting, Outlook automatically downloads all Internet Calendar appointment attachments. If you disable or do not configure this policy setting, Outlook does not download attachments when retrieving Internet Calendar appointments.

ℹ️ Check
Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2016 -> Account Settings -> Internet Calendars "Automatically download attachments" is set to "Disabled". Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\16.0\outlook\options\webcal Criteria: If the value EnableAttachments is REG_DWORD = 0, this is not a finding.

ℹ️ Check

Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2016 -> Account Settings -> Internet Calendars "Automatically download attachments" is set to "Disabled". Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\16.0\outlook\options\webcal Criteria: If the value EnableAttachments is REG_DWORD = 0, this is not a finding.

✔️ Fix
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2016 -> Account Settings -> Internet Calendars "Automatically download attachments" to "Disabled".