Not a Member: GETPROPERTYBROKER error message

Problem
Not a Member: GETPROPERTYBROKER error message.

Why does this happen:
If you create a folder, from a Lotus Notes 6.x (R6) client, in a mail database that has a Lotus Notes 8 design the above error appears.

Solution:
This problem can be corrected by Upgrading the design of the mail file of the affected user who is on Lotus Notes 8 by clicking on "Actions -> Folder -> Upgrade Folder Design...".
Please ensure the end user is out of the mail database before pressing the "Automatic Updrade" button.

Once you have done the above, the error will not appear again.