Outlook OAB download fails with 0x80004005 and/or 0x8004010F
Mar08

Outlook OAB download fails with 0x80004005 and/or 0x8004010F

KB ID 0000035  Problem 0x8004010F is caused by client not being able to see the Offline Address Book. 0x8004010F Error With Exchange 2013/2016/2019 Firstly make sure your autodiscover is correct, on the Exchange server open the Exchange management shell, and issue the following  command. Get-clientAccessServer | fl Name,AutoDiscoverServiceInternalUri If you need to fix/change it, use the following syntax. Set-ClientAccessServer...

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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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Can you Use ‘Let’s Encrypt’ on Hybrid Exchange?
Jan07

Can you Use ‘Let’s Encrypt’ on Hybrid Exchange?

KB ID 0001770 Problem A few months ago I wrote an article about getting free exchange certificates with Lets ‘Encrypt’. And that still works peachy, I implemented it on my test Exchange 2019 server (in Hybrid mode) and all appeared well.  Some time later, (remember this is my test network so it’s not in production.) I noticed that mail was not getting forwarded from O365 to the on premises Exchange server. I’ve...

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Exchange Y2KK Bug
Jan04

Exchange Y2KK Bug

KB ID 0001769 Y2KK Problem Over the last couple of days the Exchange forums have been alight with the Y2KK bug, typically it affects Exchange 2016 and 2019 (though the chatter is, it actually effects any Exchange versions whose update version begins with 22… This is fine below, (it begins with 21..) Add-PSSnapin Microsoft.Forefront.Filtering.Management.Powershell Get-EngineUpdateInformation Y2KK Symptoms  Emails No Longer Being...

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Exchange ECP HTTP 500 Error
Dec22

Exchange ECP HTTP 500 Error

KB ID 0001756 Problem This infuriatingly happens to me a lot! Every time the fix is the same, (but is a little impractical). Essentially you attempt to log in to ECP (Exchange Admin Center), you a prompted for your credentials, then you just get a ‘500 Error”.     The website cannot display the page   HTTP 500  Most likely causes: •The website is under maintenance. •The website has a programming error. What you can try:  ...

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In Place Upgrade Windows 2016 to Windows 2019
Aug11

In Place Upgrade Windows 2016 to Windows 2019

KB ID 0001761 Problem For the last twenty years or so I’ve said “In place upgrades are a bad idea”, my rationale has been that if something is broken we are simply migrating that problem, and we are relying on a lot of factors, (some of which may be unknown.) That we will just have to ‘trust that it will work’. Most modern servers are virtual so we can snapshot them, or clone them and test the upgrade...

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