Hi,
Are you by any chance running jira behind a reverse proxy? In this case post the proxy configuration, so we can help you on this.
If you're running jira standalone, check /path/to/jira/config/server.xml and make sure you have an empty Context path:
Code:
...
<Context path="" docBase="${catalina.home}/atlassian-jira" reloadable="false">
...
Regards