Roundcube 1.0.0 - problem with raw message headers

[Thunderstick]

Hello,

when i want to toggle the raw message headers in Roundcube 1.0.0 i get the error "Could not load message from server."
This is the entry in the imap logfile:

Code Select Expand

[10-Apr-2014 19:04:44 +0200]: [CB3D] S: * OK [CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA IDLE ACL ACL2=UNION STARTTLS] Courier-IMAP ready. Copyright 1998-2010 Double Precision, Inc.  See COPYING for distribution information.
[10-Apr-2014 19:04:44 +0200]: [CB3D] C: A0001 LOGIN XXXX XXXXX
[10-Apr-2014 19:04:44 +0200]: [CB3D] S: A0001 OK LOGIN Ok.
[10-Apr-2014 19:04:44 +0200]: [CB3D] C: A0002 SELECT junk
[10-Apr-2014 19:04:44 +0200]: [CB3D] S: A0002 NO Mailbox does not exist, or must be subscribed to.
[10-Apr-2014 19:04:44 +0200]: [CB3D] C: A0003 LOGOUT
[10-Apr-2014 19:04:44 +0200]: [CB3D] S: * BYE Courier-IMAP server shutting down
[10-Apr-2014 19:04:44 +0200]: [CB3D] S: A0003 OK LOGOUT completed


Any ideas?
Many thanks in advance.

[Thunderstick]

No one else got this problem or have a solution?