Group Won’t Accept Mail From ‘Outside’
Jan10

Group Won’t Accept Mail From ‘Outside’

KB ID 0001771 Problem Exchange has been this way for a long time here’s me explaining this very problem with older versions of Exchange. If you create a ‘Group’, be that a Distribution Group, or a ‘Microsoft 365′ Group, the default setting is to NOT ALLOW mail from anyone outside your organisation. If you attempt to send mail to that group you will see errors like these; Errors; 550 5.7.133...

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Exchange: PowerShell Commands
Feb26

Exchange: PowerShell Commands

KB ID 0001405 Problem This might seem like an odd title for an article here at PNL? But I’m going to use this page as a place to put all the commands I’m sick of Googling for, and/or working out every time I do an Exchange job. So as with all the posts here, it’s here for my benefit, and if anyone else gets something from it great! Exchange General Change Exchange Licence Code Set-ExchangeServer -Identity Server-Name...

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CentOS – Setup the iptables Firewall
Nov17

CentOS – Setup the iptables Firewall

KB ID 0000938 Problem I was a little perturbed to find out the firewall on my CentOS web server was wide open today. My server setup notes yielded no clues, so it was time to put my ‘Linux Head’ on and fix it. Solution 1. Connect to the server via console or SSH. As I’m going to change the iptables config file lets back it up (always assume you are going to smash something!) cp /etc/sysconfig/iptables iptables.bak 2....

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