[imp] Fwd: Authentication for a mail service

[Arjen de Korte]

> In my settings of mail server, I use self signed certificate (  
> /etc/imapd.conf ).
> When I try to login to horde webmail, it returns me back to login page.
> Therefore I use horde/imp/test.php. After input my login data, I get this:
> * Trying protocol imap/notls, Port 143:  SUCCESS
> * Trying protocol imap/ssl, Port 993: ERROR
>   Certificate failure for localhost: self signed certificate in  
> certificate chain: /data of certificate authority(O,OU,CN...)/

It looks like you didn't import the root CA you used for creating your  
self-signed certificate into the list of trusted CA's (typically found  
in /etc/ssl/certs, depending on the distribution you're using). This  
needs to be done on both the server running IMAP and the server  
running Horde IMP (if these are on different systems).

> * Trying protocol imap/ssl/novalidate-cert, Port 993:  SUCCESS
> * Trying protocol imap/tls/novalidate-cert, Port 143:  SUCCESS
>
> I don't give the file with certificate autorithy to horde, because I  
> don't know it is possible or necessary.
> How can I solve this problem, please?

Make sure that the root CA you used is trusted. You can verify this by running

     openssl s_client -connect imap.example.com:993
     openssl s_client -connect imap.example:143 -starttls imap

Note that you should be running the above commands from the system  
running Horde to the system running IMAP.

Best regards, Arjen