no email received

I have been using jmailAlerts successfully for a while and love the functions it offers. Recently though no emails are being received. I took the opportunity to uninstall the previous version and install 2.5 which work with no problems. I followed the documentation and tried a simulation.

I receive the mail sent message but nothing arrives in my inbox. I have ran the CRON job from the URL and the log says it successfully sent to users but no email is received. Im not sure where to check next..