Do not validate personal distribution lists when sending e-mail messages

Use only the local cache to obtain current user information when expanding a Personal Distribution List while sending e-mail

Supported on: At least Windows Vista
Registry HiveHKEY_CURRENT_USER
Registry PathSoftware\Policies\Microsoft\Office\12.0\Outlook\Options\Mail
Value NameExpandPDLUsingCache
Value TypeREG_DWORD
Enabled Value0
Disabled Value1

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Administrative Templates (Computers)

Administrative Templates (Users)