How can I enable/disable the "Conversation" feature?
To view the message in Conversation View you have to enable this feature. Viewing messages in Conversation View might slightly slow down viewing of messages. This is why you might want to disable this feature.
To enable/disable the Conversation feature, please do the following:
Select the "Settings" tab and the "General Settings" option in the left menu.
Select the "Enable conversations" checkbox in the "Viewing messages" section to enable this feature or leave it empty to disable it.