Well,

the sheet does exist at the time I run my macro - it is prepared every day before 8 o' clock.
The output of the DATE function is formatted like that, at least it is when I output it in a MsgBox.
You're right, I don't need to activate the sheet, just like I don't need to SELECT cells all the time just to put some values into them. It just makes the code a lot easier to read (for not-savvy others), which is one of my primary development standards.

So, what can I do, or how could I make sure the date is formatted like I need it?

Thanks a lot!