tlsv1 alert unknown ca: SSL alert number 48

[Maurizio Dall'Acqua]

I have found a solution!

I have tried to install the new version or Roundcube from github, but I have
had some problems with the configuration files. So I've switched back to
Squirrelmail.

I have set Squirrelmail to plain text login but I have tunneled the
connection to stunnel4 by means of xinetd, so I can have a secure login
connection. For some reasons both Roundcube and Squirrelmail can't use the
self-signed certificate I provided, but it is not a problem for stunnel4.

So, here we go,

Thanks to all those who have suggested a solution in the mail-list.

;-) 

On Sat, Jun 18, 2016 at 10:27:50AM -0400, Gedalya wrote:
> I didn't actually test this. There might be some incompatibility preventing this from installing properly on raspbian.
> Was there nothing else printed out? Usually when you get such a line it is printed several lines below something else, where the actual problem occurred.
> Anyway, this is getting way out of the scope of this mailing list. Frankly it isn't too difficult to just manually install roundcube directly from the sources on github, and that may be your best option right now.
> 
> 
> On 06/18/2016 08:01 AM, Maurizio Dall'Acqua wrote:
> > I've tried to install the new version of Roundcube but I've got an error
> > message:               
> >
> >
> > Unpacking roundcube (1.1.5+dfsg.1-1~bpo8+1) ...
> > Errors were encountered while processing:
> >  /var/cache/apt/archives/roundcube-core_1.1.5+dfsg.1-1~bpo8+1_all.deb
> > E: Sub-process /usr/bin/dpkg returned an error code (1)
> >
> > If anybody can give me instructions on how to correct this, perhaps I should
> > try to downgrade again?
> >
> >
> >
> > On Sat, Jun 18, 2016 at 06:37:33AM -0400, Gedalya wrote:
> >> On 06/18/2016 02:27 AM, Maurizio Dall'Acqua wrote:
> >>> The version of Roundcube I am using is 0.9.5+dfsg1-4.1
> >> If you want to get a newer version using Debian packages, perhaps try to add the following line to /etc/apt/sources.list :
> >>
> >> deb http://httpredir.debian.org/debian jessie-backports main
> >>
> >> Then run:
> >>
> >> apt-get --dry-run -tjessie-backports install roundcube
> >>
> >> and take a close look at what's being pulled from where, make sure it all makes sense to you.
> >>
> >> Then run it again, for real:
> >>
> >> apt-get -tjessie-backports install roundcube
> >>
> >> This should get you roundcube 1.1.5+dfsg.1-1~bpo8+1 from Debian's repository, while pulling necessary dependencies from your native raspbian.