Well I've heard back from Brother and they suggest that my SElinux set up has a problem. They recommended that I do
semodule -vR
This gave me exactly the same error messages. Then I did semodule -vB which worked OK, but repeating semodule -vR still gives

[root@ferguson src]# semodule -vB
Committing changes:
Ok: transaction number 0.
[root@ferguson src]# semodule -vR
SELinux:  Could not downgrade policy file /etc/selinux/targeted/policy/policy.29, searching for an older version.
SELinux:  Could not open policy file <= /etc/selinux/targeted/policy/policy.29:  No such file or directory
/sbin/load_policy:  Can't load policy:  No such file or directory
libsemanage.semanage_reload_policy: load_policy returned error code 2. (No such file or directory).
[root@ferguson src]# 

This is happening on two different SL 7.2 machines with SElinux installed but disabled.

I even tried uninstalling selinux* but that got me into deeper trouble.

[root@ferguson src]# rpm -qv selinux-policy
selinux-policy-3.13.1-60.el7_2.7.noarch

Is there an issue with this version of selinux???

Cheers
Bill

-----Original message-----
> From:Bill Maidment <[log in to unmask]>
> Sent: Saturday 25th June 2016 17:26
> To: Akemi Yagi <[log in to unmask]>; SL Users <[log in to unmask]>
> Subject: RE: SL7 CUPS/SELinux problem trying to install Brother HL-3150CDN printer driver
> 
> Thanks for the suggestion Akemi.
> Unfortunately, it made no difference.
> I'm awaiting comment from Brother, but I suspect they will say change to Ubuntu :-(
> Cheers
> Bill 
>  
> -----Original message-----
> > From:Akemi Yagi <[log in to unmask]>
> > Sent: Saturday 25th June 2016 1:10
> > To: SL Users <[log in to unmask]>
> > Subject: Re: SL7 CUPS/SELinux problem trying to install Brother HL-3150CDN printer driver
> > 
> > On Fri, Jun 24, 2016 at 2:33 AM, Bill Maidment <[log in to unmask]> wrote:
> > > Has anyone any suggestions how to get a Brother HL-3150CDN printer driver installed on SL7.
> > > I have been trying to install using the Brother supplied installation script, which worked OK on SL6.
> > >
> > > With SL7 I get error messages such as:
> > > SELinux:  Could not downgrade policy file /etc/selinux/targeted/policy/policy.29, searching for an older version.
> > > SELinux:  Could not open policy file <= /etc/selinux/targeted/policy/policy.29:  No such file or directory /sbin/load_policy:  Can't load policy:  No such file or directory
> > >
> > > The file in question does exist, but I have selinux disabled anyway.
> > >
> > > SL7 is using cups version 1.6 whereas SL6 uses cups version 1.4. Is that an issue?
> > > I guess the Brother script is a bit out of date as it was created in 2012.
> > >
> > > Any help would be appreciated.
> > >
> > > Cheers
> > > Bill Maidment
> > 
> > Can you try reinstalling selinux-policy packages and see if that fixes
> > the issue?
> > 
> > yum reinstall selinux-policy\*
> > 
> > Akemi
> > 
> >