Calendar doesn't send email alerts on Mavericks
There used to be a great feature of Calendar application. It could send emails as alerts to remind of the events.
But after upgrading to OS X Mavericks (10.9) things have been spoiled up. Now calendar application doesn't send email alerts anymore.
Neither existing nor new email alerts work properly. I've checked everything in Settings. Network is working just fine. Mail application is able to send and receive emails. I use MacBook Pro, mid 2012.
Does anybody know, what shall I try? Would appreciate any help. Thanks.
MacBook Pro, OS X Mavericks (10.9)