Issue: when Outlook 2007/2010 attempts to download the offline address book via CAS Web Distribution the following error is recieved:
Task 'Microsoft Exchange' reported error (0x80190197) : 'The operation failed'
This error occurs when Outlook attempts to download the offline address book through a proxy server. This is heavily identified... please see:
However today I found another scenario which produces exactly the same error. My clients internally download the OAB through HTTP and externally they download the OAB via HTTPS.
In IIS7 go to the OAB Virtual Directory and click SSL Settings.
Untick Require SSL as internal clients are trying to download the OAB without SSL encryption.
Apply the settings.