Emails never received

It worked in CS 2.1 Beta 1 but then it suddenly stopped working. I have upgraded to CS 2.1 RC 1 but I still don't receive the automated emails. When someone posts a comment on one of my blog entries. I see the record being added to the table cs_EmailQueue, after a couple of seconds the record is removed and in the table cs_EventLog I see the following entry:

Email Queue:
Messages Sent: 1
Messages Failed: 0

But for some reason I no longer receive any email from my blog. I also don't receive emails when I use the Mass Mailing feature. What could be wrong?

Have you looked in the exceptions report for anything corresponding to the emails?  Can you track them in your mail server to verify it received them and see what it did with them?

It is a hosting package on Hostbasket. I have created a test page that sends out emails, I receive no exceptions but the mails are never received. Therefore I believe that there is a problem with the server. All mails are propably queued and waiting to be send.

Also, why don't i receive emails from this forum when somebody replies to my post? I have enabled email subscriptions yet i don't receive emails. 

For your site, go to the Control Panel, and go to Administration, Settings, Email Settings.  Is "Enable Email" set to Yes?  If not, change it.  I noticed that value is defaulting to false, so I submitted a request to change it.  It is likely the cause of why the email queue has messages, but the job is not sending them.

As for notifications from this site, you should go view your user profile and under Email, make sure Receive Emails is enabled.  Notifications are working, since I read your post in the notification.  Also, when viewing the thread, at the top of the first pst, there should be a "Disable Email Subscription", which means you are already subscribed.