If you didn’t start from scratch yet - when you tried older versions, did you uninstall the current one beforehand, or just installed one over it? The latter might cause issues, like it did in my case. Just in case you didn’t already try that, you can follow reinstall instructions here: Synology FAQ (DSM 5 & 6) - Questions, Answers, and a few How-To's - #14 by ChuckPa
