Hallo,we applied in Default Domain Policy that Outlook Cache Mode is automaticly used for all Clients.But this leads to the problem, that the cache files on a Terminalserver fills the Systemdrive.So we wrote a local script (which is only executed on Terminalserver User login) that the cache mode is disabled through Registry [HKCU\Software\Policies\Microsoft\Office\Office Version Number\Outlook\cached mode DWORD: Enable 0It works for new Users which are logging on to the Terminalserver.It works also for existing Users/Profiles (the Registry Key is correct set to 0 -> and in the Outlook Profile the Cache Mode Option is not checked,but even if we delete the .ost file every time the User opens Outlook (2010) the cache fil will be build again and is filling.Resolution would be to delete the whole User Profile (on the Terminalserver) and create a new one.But thats not practical for us (because there are about 100 existing Profiles).RegardsRainer