Hello

We have ZOHO Professional and plan on using this CRM to organise large volumes of students, we need to be able to send mass communications to groups of different students based on their qualification and company etc. From the Deals tab (we have customised this to contain students instead of deals) we have tried to send mass emails based on specific company criteria but every time it doesnt work- I get the below message sent to my email. 

Could someone please help? We set up the criteria, attach the message etc so cant work out why this feature is not working.