Outlook 2010 autocomplete stopped completing for Office365 user. Other users on the same Office365 subscription are okay. The actual stream_autocomplete file under username\AppData is there, and the modification date is updated appropriately when Outlook closes. The actual autocomplete feature isn't working.
I created a new Outlook profile. The behavior remains.
I tried the Fix It here:
It just renames the RoamCache to old_RoamCache and creates a new set of folders. The behavior remains.
I toggled the checkbox under Options, Mail, Send Mail, use Autocomplete.
The behavior that I'm seeing suggests this checkbox isn't working.
I know Microsoft Outlook's autocomplete is a convenience, intended for temporary use, support is incomplete via Microsoft and Office365. The user demands this feature, and I'm supporting it.
Your advice would be appreciated. The user gets adequate choices with Check Username button, but only wants autocomplete.