smtp_debug output on Windows Server with IIS?

I'm trying to figure out a brand new SMTP issue that is occurring with our bugzilla installation: Windows Server 2012, IIS, and the standard install package of perl and bugzilla. All users are now seeing:

"There was an error sending mail from 'someone' to 'someone else': unable to establish SMTP connection to ...."

I suspect that corporate IT is up to some shenanigans and broke something (it's happened before).  So I went to the IIS log files, and they show nothing about an SMTP error. I enabled smtp_debug - I can find no additional information. Where is the SMTP debug output?

FWIW, I can ping and telnet into the smtp server. It seems to be working fine.

Reads like firewall, maybe application level for IIS only?

It's simply printed to STDOUT or STDERR, not sure currently. In case of Apache HTTPd things are logged to default error_log files in the end. Neither Bugzilla nor SMTP-libs use some additional special other file, so if you find nothing in Event Viewer etc., have a look at your setup regarding STDOUT+STDERR.

Thortsen,

I had not thought of the firewall issue. Any time a web server gets involved, things get tricky. STDERR/STDOUT - I'll track this down and for the sake of Bugzilla follow up with what I find.

Charles

Okay, issue is resolved. Thortsen your clue about the web server gave me some ideas as to where the problem might be. Last week, IT was debugging another issue on this machine and turned off CGI Impersonation. Flipping it back on and restarting the web server resolved the issue.