For a support system it's quite normal for users to expect to submit issues by email, not have to use a web interface.
Under email settings ( Project administration ) for service desk ( above 2.0 version ) , you can select issue type and the email id that you would like to configure can be set up.
See https://confluence.atlassian.com/servicedeskcloud/receiving-requests-by-email-747602718.html
Thanks for the answer, but I'm afraid it doesn't work.
But when I click on the button and set a password, I end up at a blank homepage:
Hmm, that sounds like there's a problem on Cloud. I'd raise that with Atlassian support, because it looks like you've done everything right to me, and it's the Cloud JIRA falling over.
It looks like you're new here. Sign in or register to get started.