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If you run web servers that need to be able to send e-mails but don't want the hassle of running a SMTP server or are worried it may be blocked as "untrusted" if you're hosting on a ADSL line then you may be interested in nullmailer. Postfix and exim4 do allow use of smart hosts but it's not terribly easy to set up AUTHENTICATED smart hosts and it seems to be overkill to run a full SMTP server simply to allow PHP to send e-mail. Step in nullmailer, simple configuration for authenticated and unauthenticated smart hosts and everything is relayed via the SMTP server of your ISP or hosting company. I'd suggest setting up a dedicated mail account for the purpose so you don't break things by changing your mail password. Index of nullmailer

Hi, To stop anyone else having the same 'fun' as me, I thought I would share my Windows 7 problem that has resulted in many hours spent testing different DHCP servers, routers, NICS and reviewing packet logs! This problem seems to occur if you have all of the following: Using a DHCP reply to forward DHCP requests (e.g. using VLANs and an IP helper on the router to forward DHCP requests) Windows 7 clients Windows Firewall Public Profile turned on (default configuration - all profiles) DhcpConnForceBroadcastFlag = 0 (Default for Windows 7) Symptoms NETLOGON event ID 5719 in system event log This computer was not able to set up a secure session with a domain controller in domain due to the following: There are currently no logon servers available to service the logon request. Group policies inconsistently applying on start-up Event ID 50024 logged in the Microsoft-Windows-DHCP Client Events/Operational event log (you need to enable this event log as its disabled by default) Ack Receive Timeout has happened in the Interface Id xx Background By default Windows 7 request for its DHCP reply's to be a uncast responses. If you are using a Windows DHCP server and your client is on the same broadcast domain (not accessing the DHCP server via a DHCP reply) the DHCP server receives the request but ignores the clients request for a uncast response, and reply's in a broadcast. In this situation everything works. The problem occurs when your client has to access the DHCP server via a DHCP relay, such as a router or switch and the DhcpConnForceBroadcastFlag registry key is still set to the default(0). In this situation, the client sends out a broadcasts requesting an IP address, the DHCP relay forwards the request to the DHCP server, the DHCP server sends the reply(ACK reply) to the relay and the DHCP relay sends a uncast reply to the client. If the Public profile is turned on in the Windows Firewall (on by default) then the ACK reply is dropped by the firewall and is never passed to the DHCPclient.dll Conclusion I passed my findings and research to Microsoft support and after more packet logs and deep Microsoft DHCP\Firewall traces, they have concluded it's a bug! they have now created an internal KB for this problem. This has now been passed to the developers and I am awaiting an acceptable workaround and Microsoft to release a patch. I will post the workaround and a link to the patch when I get more information from Microsoft. Hope this helps, Edd

Helloo, not sure if anyone can help, but the past month across our whole deployment of 1000 Macs, we've been getting specific pages blocked at random 'Due to a filtering service problem'. These are fully allowed at the top level. We've had a Lightspeed engineer check over our deployment on Jamf, remote onto a machine, and all appears correct. At this time they're unsure of whats causing it. The issue happens more frequently when going to links without 'www.' in the URL. Such as 'https://amazon.co.uk/' will be blocked, but 'https://www.amazon.co.uk/' will be allowed, despite traffic in relay saying its allowed to both. Then there is a long list of sites we've got where both options do not work. We've tried different DNS servers, and get the same thing. Our Windows and Chrome devices are all working fine. Enabling the 'bypass rules on failure' does get it working correctly, but we don't want that option enabled for security reasons. Its at the point where we've now got the whole school on our back about it... Any ideas are greatly appreciated.

Having a bit of a strange problem with our web filter agent blocking the saving of Bitlocker Recovery keys to Azure. Has anyone else experienced this? I can't seem to find anything online about what might be causing this and the devices don't show any obvious traffic during this time.

I'll explain the complicated setup I have initially... 1. LancsNGfL mailserver accepts mail destined for our domain 2. The LancsNGfL mailserver then relays that mail to an IP address 3. The IP address mentioned in 2 is then nat-ed with a port forwarding rule to my Zimbra server 4. If the Zimbra server does not have the recipient, the mail is relayed onto my Exchange server Now the problem... I'm decommisioning the Zimbra server so there's now no accounts on it. My Exchange server is sat happily receiving mail. If I change the port forwarding rule to point to the exchange server (which has a recipient rule on it accepting mail from thew LancsNGfL relay), I stop receiving mail. Changing the port forwarding rule back fixes the problem. What am I missing?