Problem with 'set folder'

[Til Schubbe <t.schubbe@xxxxxx>]

Hi,

I've set up mutt 1.5.9i on a new linux computer. In the rc I have

set folder=~/mail

But on mutt's startup it shows the - non existing - content of
/var/mail/$USER.

How can I tell mutt to immediately switch to $folder at startup and
show the Maildirs in it?

TIA
Til