For informations, here is an extract from cups error log with Loglevel=debug2. This extract is when i assign a specific printer to be the default printer.
D [27/Apr/2006:21:48:00 +0200] CUPS-Get-Default d [27/Apr/2006:21:48:00 +0200] get_default(0x80ec7c8[8]) d [27/Apr/2006:21:48:00 +0200] cupsdFindPolicyOp(p=0x80b9f18, op=4001(CUPS-Get-Default)) d [27/Apr/2006:21:48:00 +0200] cupsdFindPolicyOp: Found wildcard match... d [27/Apr/2006:21:48:00 +0200] cupsdIsAuthorized: con->uri="/", con->best=0x80bb0d8((null)) d [27/Apr/2006:21:48:00 +0200] cupsdIsAuthorized: level=AUTH_ANON, type=AUTH_NONE, satisfy=AUTH_SATISFY_ALL, num_names=0 d [27/Apr/2006:21:48:00 +0200] cupsdIsAuthorized: op=0(unknown-0000) d [27/Apr/2006:21:48:00 +0200] cupsdIsAuthorized: auth=AUTH_ALLOW... I [27/Apr/2006:21:48:00 +0200] CUPS-Get-Default client-error-not-found: No default printer D [27/Apr/2006:21:48:00 +0200] cupsdProcessIPPRequest: 8 status_code=406 (client-error-not-found) d [27/Apr/2006:21:48:00 +0200] cupsdProcessIPPRequest: Adding fd 8 to OutputSet... d [27/Apr/2006:21:48:00 +0200] cupsdWriteClient: 8 bytes < 0 d [27/Apr/2006:21:48:00 +0200] cupsdWriteClient: Removing fd 8 from OutputSet... d [27/Apr/2006:21:48:00 +0200] cupsdAcceptClient(lis=0x80bd478) 2 Clients = 3 D [27/Apr/2006:21:48:00 +0200] cupsdAcceptClient: 10 from localhost (Domain) d [27/Apr/2006:21:48:00 +0200] cupsdAcceptClient: 10 connected to server on localhost:631 d [27/Apr/2006:21:48:00 +0200] cupsdAcceptClient: Adding fd 10 to InputSet... d [27/Apr/2006:21:48:00 +0200] cupsdReadClient: 8, used=0, file=-1 state=0 d [27/Apr/2006:21:48:00 +0200] cupsdReadClient: httpGets returned EOF... D [27/Apr/2006:21:48:00 +0200] cupsdCloseClient: 8 d [27/Apr/2006:21:48:00 +0200] cupsdCloseClient: Removing fd 8 from InputSet and OutputSet... d [27/Apr/2006:21:48:00 +0200] cupsdReadClient: 10, used=0, file=-1 state=0 D [27/Apr/2006:21:48:00 +0200] cupsdReadClient: 10 POST / HTTP/1.1 d [27/Apr/2006:21:48:00 +0200] cupsdFindBest: uri = "/"... d [27/Apr/2006:21:48:00 +0200] cupsdFindBest: Location CUPS_INTERNAL_BROWSE_ACL Limit 0 d [27/Apr/2006:21:48:00 +0200] cupsdFindBest: Location /admin/conf Limit 7f d [27/Apr/2006:21:48:00 +0200] cupsdFindBest: Location /admin Limit 7f d [27/Apr/2006:21:48:00 +0200] cupsdFindBest: Location / Limit 7f d [27/Apr/2006:21:48:00 +0200] cupsdFindBest: best = / ** Attachment added: "CUPS-Get-Default.txt" http://librarian.launchpad.net/2392495/CUPS-Get-Default.txt -- root privileges needed to set default printer https://launchpad.net/bugs/41304 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs