Email won't send over Wifi

I’m having a weird issue with my eM Client. For some reason, emails won’t send when i’m on Wifi, but when I connect to ethernet all the emails will send. The emails remain in the inbox, unsent until connecting to ethernet. Has anyone ever experienced this issue?

Your wifi network is blocking SMTP connections. This is done in some networks to prevent the spreading of viruses through e-mail. Talk with your IT managers to confirm it.