Vodacom has decided to follow the lead of iBurst and MWeb to (for some of their data packages) block SMTP access to third parties (like Anno) on port 25. If you are a Vodacom subscriber, please use port 587 instead to connect to our SMTP servers. Alternatively send your email through Vodacom’s SMTP server at smtp.vodacom.co.za or smtp.vodamail.co.za.
See our Knowledgebase article for more email troubleshooting tips.