[tlug] mutt no mailbox error

["Kohama" <y-kohama@example.com>]

Hi,

Anyone help me out related to MTA setting problem?

I just started using mutt as MUA.
Default mailbox type is mbox but I changed it to Maildir
to sort mails to various folders with using procmail.

I added four lines on $HOME/.muttrc file like followings :

set mbox_type=Maildir
set spoolfile="/home/kohama/Mail"
set folder="/home/kohama/Mail"
set mbox="/home/kohama/Mail/mbox"

Then,when I start mutt, it doesn't work properly anymore.
I can't download incoming mail from pop server anymore.

I can still open default mailbox "$home/mbox" by choosing it , but
I never be able to open newly set mailbox"$home/Mail"

Mutt always says followings as an error :

"/home/kohama/Mail is not a mailbox."

Does anyone know how to fix this error?

Thanks,
Yuki