Issues connecting to outlook

Issues connecting to outlook

Each time I try to connect one of the 5 users I have for my Zoho account to outlook, I get the following issue message. 
I have tried with all 5 users, using the passwords I use to log into zoho webmail, but get the error message seen in the attachment each time. 
I cannot stress enough times that this is not me inputting the password wrong. 
Any advice?