Activate SSH
Connect via SSH with either
ssh root@IP
or
ssh admin@IP
and sudo su
Change VERSION file as needed.
vi /etc.defaults/VERSION
Change:
6.0
to5.0
6
to5
7274
or similair to5434
Close editor withESC :wq ENTER
Login at Diskstation and do a manual update to a 5.x version. Restart Diskstation and do a Factory reset.
Have fun with your reverted and stable Diskstation! :)