Some steps are missing for offline upgrade

9th point should be restoring the backup of the data.
Please mention the commands to backup and restore the information from cbbackupmgr.

cbbackupmgr config [options] -> Creates and configures a new backup repository.

cbbackupmgr backup [options] -> backup the data.
cbbackupmgr restore [options] -> to restore data.

Offline update on windows from 4.x to 5.x required to uninstall 4.x completely before installing 5.x. Backup directory should be outside the couchbase directory since uninstalling previous version will remove all files created(On windows).