Problem mail

Hello, I have a problem with mail notifications. It as already worked but now it doesn't.

I tried with the port 25 and 587

I tried severals things, on projeqtor and on the firewall of the internet box but I don't find where does the problem come from.

See the log files

2016-06-02 16:57:01.072 ***** ERROR ***** ERROR *****
2016-06-02 16:57:01.076 ***** ERROR ***** on file '/volume1/web/projeqtor/external/PHPMailer/class.smtp.php' at line (344)
2016-06-02 16:57:01.081 ***** ERROR ***** cause = stream_socket_enable_crypto(): Peer certificate CN=`ssl0.ovh.net' did not match expected CN=`smtp.blaise-industries.fr'
2016-06-02 16:57:01.192 ***** ERROR ***** Error sending mail
2016-06-02 16:57:01.198 ***** ERROR ***** SMTP Server : smtp.blaise-industries.fr
2016-06-02 16:57:01.207 ***** ERROR ***** SMTP Port : 587
2016-06-02 16:57:01.211 ***** ERROR ***** Mail stored in Database : #161
2016-06-02 16:57:01.216 ***** ERROR ***** PHPMail error : SMTP connect() failed. github.com/PHPMailer/PHPMailer/wiki/Troubleshooting
2016-06-02 16:57:01.221 ***** ERROR ***** PHPMail debug :
2016-06-02 17:04:44.164 ***** ERROR ***** ERROR *****
2016-06-02 17:04:44.168 ***** ERROR ***** on file '/volume1/web/projeqtor/tool/projeqtor.php' at line (936)
2016-06-02 17:04:44.172 ***** ERROR ***** cause = Undefined variable: logLevel
2016-06-02 17:04:50.213 ***** ERROR ***** ERROR *****
2016-06-02 17:04:50.219 ***** ERROR ***** on file '/volume1/web/projeqtor/external/PHPMailer/class.smtp.php' at line (344)
2016-06-02 17:04:50.224 ***** ERROR ***** cause = stream_socket_enable_crypto(): Peer certificate CN=`ssl0.ovh.net' did not match expected CN=`smtp.blaise-industries.fr'
2016-06-02 17:04:50.306 ***** ERROR ***** Error sending mail
2016-06-02 17:04:50.311 ***** ERROR ***** SMTP Server : smtp.blaise-industries.fr
2016-06-02 17:04:50.317 ***** ERROR ***** SMTP Port : 25
2016-06-02 17:04:50.323 ***** ERROR ***** Mail stored in Database : #162
2016-06-02 17:04:50.327 ***** ERROR ***** PHPMail error : SMTP connect() failed. github.com/PHPMailer/PHPMailer/wiki/Troubleshooting
2016-06-02 17:04:50.331 ***** ERROR ***** PHPMail debug :