Customer Login Alert - Token is either expired or not valid

[satish kumar venu]

We have created Customer to access out Jira servicedesk Customer page . 

When they try to log in for the first time they get the message "Token is either expired or not valid" . 

please note that the customer tried to login within a hour of creation of the customer login. 

[Andy Heinzer]

1. What version of Jira Service Desk is this?
2. What steps did you take to create the account/invite this user?
3. Is it possible the Jira Server's system clock is askew from that of the user being invited (I'm not concerned if the timezones are different, but if the system clock is 5 minutes or more adrift from the actual time, then it could be that certificates/tokens like this would be invalid.)
4. Did the user have to click a link to complete the sign up?
5. Is this user able to go directly to $JIRAURL /servicedesk/customer/user/signup in order to complete this account creation that way?