[cups] Difficulty in Adding a printer

[Alan McConnell]

Assembled Wisdom!

My difficulty is one which it seems others have had:  I wish to
add my new Brother printer: but when I try to do it from the GUI
(http://localhost:631, I get the message, in a little pop-up box:
"A username and password are being requested by http://localhost:631.
The site says: "CUPS"".   I have entered my ordinary user name 'alan'
with password, but the box returns; I have entered 'root' and the
root passwd, but the box returns.

My system info:
Linux Debian 'Wheezy'
CUPS 1.5.3

I have also tried, from the command line(as root)
   lpadmin -p laserjet -E -v usb:/dev/lp1 -m BrGenML1.ppd 
and get the error message:
  lpadmin: Unable to copy PPD file.
However, I have downloaded, from the Brother site, a .deb file
which, when dpkg-ed put a file   BrGenML1.ppd  into the directory
/etc/cups/ppd/.

TIA for anticipated assistance!

Alan

-- 
Alan McConnell :  http://globaltap.com/~alan/
       They finally got King Midas, I hear.  Gild by association.
       What a giftless bastard! (Tchaikovsky, about Brahms)