email does not work

I don't receive email notifications. In particular, I checked

IOError at /account/recover/

[Errno 5] Input/output error

Request Method: POST Request URL: http://website.com/account/recover/ Django Version: 1.5 Exception Type: IOError Exception Value:

[Errno 5] Input/output error

Exception Location: /usr/local/lib/python2.7/dist-packages/askbot/mail/__init__.py in send_mail, line 146 Python Executable: /usr/bin/python

What can be the reason that it doesn't work? I also installed some email programs (like dovecot).

my server is also hosted at a company. it is possible the ports are blocked? But I assume they just use basic ports (22, etc.)

thanks in advance