SmartWare - username and password

I installed SmartWare last month. When I was ready to use it today, the backup tab was greyed out. It says to enter login credentials, username and password. But for the life of me, I cannot remember either!

Change the destination folder to the default WD SmartWare folder. The application should not ask for credentials unless the target folder is a private share within your WD My Cloud (And if it is, it should accept the username and password for said private share).

Thanks. But I think you need to be clearer. When you say ‘destination
folder’ do you mean in the Home tab, it is the ‘Backup Target’ in the
right panel? If so, when selecting either the name of the folder I
created in the device or ‘Smartware’ the ‘Backup’ tap still remains
greyed out. Only when selecting ‘TimeMachineBackup’ can I select the
‘Backup’ tab. What do I do then? How do I backup the files from my PC to
WDMyCloud?
Peter