a question about certificates from letsencrypt

[Adrian Minta]

On 08/19/2016 04:30 PM, Sven Strickroth wrote:
> Am 19.08.2016 um 14:40 schrieb Adrian Minta:
>> The cert doesn't work with old clients.
> What do you understand under old?
>
> Ok, Windows XP clients might be problematic regarding SNI and used
> ciphers, but starting with Vista all clients which use the Windows
> CryptoAPI and Trust Store are working.
>
> Take Mozilla, there is it supported since Firefox 2.0 (I don't know
> right now which is the corresponding Thunderbird version, but I expect
> it to be supported since really early versions).
>
> Java clients are problematic as you need the latest version.
>
> Android works with >= 2.3.6 and iOS iOS >= 3.1.
>
> See
> https://community.letsencrypt.org/t/which-browsers-and-operating-systems-support-lets-encrypt/4394?u=mrtux
> for a fuller list and feel free to report more working or not working
> clients, I'll add them there.
>
> MTAs usually don't validate the certificates, so there should be no problem.
>

I did encounter some problems last year with Outlook on older Windows XP 
machines.
The problem seems to be discussed here:
https://community.letsencrypt.org/t/help-needed-windows-xp-support/8756
https://community.letsencrypt.org/t/upcoming-intermediate-changes/13106



-- 
Best regards,
Adrian Minta