I have a laser printer installed on a Linux box which is working from
Linux correctly. I can also print from other Linux machines in the
network via CUPS. One of the machines in the network runs Windows. I
shared the printer via Samba, so that Windows can “see” it via
standard Windows networking. Windows has driver for this printer
installed, but CUPS won’t allow it to print. The trick is to configure
CUPS to allow “raw” data to be sent directly to printer. To do this,
edit the file /etc/cups/mime.convs and uncomment this line (it’s near
the end of file):

application/octet-stream application/vnd.cups-raw 0 -

Depending on the default CUPS setup for your machine, you might also
need to edit the file /etc/cups/mime.types

After this, just restart CUPS and you can print from Windows box

/etc/rc.d/rc.cups stop
/etc/rc.d/rc.cups start