There's an interesting little bug in Notes mail 8.0/8.5.
On some clients, whenever you open mail, the following error dialog pops up: "Notes Error: Specified command is not available from the workspace"
This is a nuisance error; it doesn't appear to have any impact on the client.
There are precisely 2 related threads in the Notes/Domino 8.0 forums. There are none in the Notes/Domino 8.5 forums. There are no solutions.
I think I've found one, though.
The error seems to be related to a database launch property, "Restore as last viewed by user." Switch this off, the dialog goes away. Of course, I've only been able to test this on my computer, I need to repeat the test on other machines that have this problem.