I've just successfully completed upgrading Jira from 5.0 to current. So trying to do the same with confluence from 4.1.6 to current.
Here are some details:
-new server running RHEL 7
-installed same version as our production confluence 4.1.6 -- running successfully
-used file system backup method to load 'xmlreport...zip' which appeared to upload successfully. This prompts me to login again to confluence.
-attempts to login fail. (note: production confluence is authenticated by jira -- not sure if this is an issue). I can login to both my production jira and my new server sandbox jira still.
-Trying to follow: https://confluence.atlassian.com/conf64/restore-passwords-to-recover-admin-user-rights-936511358.html
Am I on the right track? Is there a better way to do this?
Thanks in advance for your help.
BTW: This isn't a case of not knowing my admin login:password and I am still able to login to the production version and my jira sandbox...so I'm not clear why this fails.
[EDIT] Ok, I think I understand how to access the confluencedb.script file now. I've tried editing this file and restarting following a number of examples from the forums. Each time I update that file and restart I get a system error with a nullpointer. I've tried both inserting the sample admin line an also replacing my admin lines. Running out of ideas. 
[EDIT #2] Just found in Conf. 4.1 Admin Docs where you can replace the hash of your admin password with the hash for 'admin'. Still no go.....but after trying this tweak to confluencedb.script at least Confluence rebooted to the login page... I am just unable to login with my known admin acct or the new passwd of admin.