When we subscribe any entry by click the "Subscribe to This Entry".
Normally, it should automatic send a notification email to the subscriber
when this entry had any changed such as reply or modify. But we tried use
this function on different users accounts but all of us cannot received
email notification. This function is very important for us as we had some
discussion folder which will have some discussion topic need to repsonse
immediately in the folder and we don't want to check it frequently on each
hour / each minutes to found out any update or reply on those discussion
entry. Could anyone can help me to solve this problem? Thanks

FYI, we can send and receive email properly when select the "Send E-mail
when entry is submitted" so we assumed our email server configuration
setting should be normally.
Server Platform: Windows 2008, Teaming 2.1