Inbound email not working although scheduler status Active

Hi all,

I has problem with InboundEmail not work it not create cases although status is Active and email account is Active.

Last run: 29.04.2016

in config_override.php I added more config 

$sugar_config['allow_pop_inbound'] = true;

Test settings successfully.

Who has this problem before and things I should focus ?

I guess it may be problem from firewall but it over my ability to deal with it.

Sugar 7.6 Ent

Thanks,

M