How to search for feature id using jql in rest api?

Vinay P V

I'm trying to write a java interface for rest api's of jira, where I want to have a where clause which contains feature id as input. But when I look at that field, it is a custom defined field.

When I pass the id of this field in where clause, I end up getting this error :

{"errorMessages":["Field 'customfield_104' does not exist or you do not have permission to view it."],"errors":{}}

The field do exist, so I guess the permission is the issue. How would I solve this problem?
I'm gracefully able to login into the JIRA system, without any authentication error.

Nic Brough -Adaptavist-

Actually, I very much doubt that field exists. Customfield tags are usually 5 digits long and start at 10000. Have another look in your installation, I think you'll find it's customfield_10004 or customfield_10400 !