Looks like that connection to port 25 for hotmail-com.olc.protection.outlook.com hostname is firewalled.
On my test Plesk server, it is open, and I see the following:
# nc -zvw3 hotmail-com.olc.protection.outlook.com 25
hosthotmail-com.olc.protection.outlook.com [104.47.57.161] 25 (smtp) open...