You set the distribution group to receive emails only from specific senders in the delivery management section of the DL properties. Now an email from external source sent to this DL and it fails with the NDR with the following error message: #550 5.7.1 RESOLVER.RST.NotAuthorized; not authorized ## Error message says it can not resolve … Continue reading Exchange: Distribution Group is rejecting emails from external email address →

Are you seeing this error on Firefox (which is common for intranet websites)? There is two reasons for this warning.  1. You may have meddled with OCSP settings. Firefox checks Certificate validity by checking “Certificate Revocation List” (CRL) using OCSP. Firefox couldn’t get the CRL info, thus this error. 2. Your internal Certificate Authority (CA) … Continue reading Firefox: Website Certificate Warning–“This website does not supply ownership information” →

From the NDR message if you find the IMCEAEX address, you CAN convert this to X500 address & ADD it as another email address to the correct mailbox or distribution group. I have wrote an small PowerShell Script to convert IMCEAEX address to X500 address quickly. Here is the script. Copy this script and paste … Continue reading Exchange: How to convert IMCEAEX to X500 Address? →

If you try Connect-Mailbox command to link the mailbox to the user account, sadly you will get this error on Soft-Deleted mailbox: Error: Mailbox "501e70da-059f-44f5-9811-77cefdfa14fd" doesn't exist on database "EXCHDBxx” I know what you thinking. Me too. Why doesn’t mailbox exist on the database?   I freaking checked the mailbox is in the database. It’s right … Continue reading Exchange: How to restore a soft deleted mailbox? →

Windows 10 Hyper-V has NAT (Network Address Translation) network feature, but it needs to setup using PowerShell now.  I will show you step by step instructions how to do it. NAT Switch provides Internet access to the VM without creating External Switch (linking the switch to physical wired or wireless adaptor). Before we start, here … Continue reading Windows 10: How to setup NAT network for Hyper-V guests? →

If you ditched an account that had a fingerprint setup in Windows Hello, Windows 10 won’t let you add the same fingerprint for another account, obliviously.  Or you are trying to use second account with same fingerprint. So you will get this error message: The question is how do we delete the registered fingerprint(s ) … Continue reading Windows 10 Hello: That fingerprint has already been set up on another account. →

I believe Outlook windows seems to hang at times due to difference between hardware or software graphics acceleration setting. By default Hardware graphics acceleration is enabled. If your Outlook goes blank or unreponsive or hangs, try disabling the hardware graphics acceleration. To do it, go to Outlook advanced settings (File ==> Settings ==>Advanced), uncheck the … Continue reading Outlook goes blank and unresponsive when new email arrives →

This information is to provide rights to unlock accounts in a OU or domain for a user WITHOUT giving any other administrative rights. so here is how to do it? Right-click the OU or domain in Active Directory Users and Computers console and select Delegate Control from the context menu Click Next on the Welcome … Continue reading Active Directory: How to delegate the right to unlock accounts? →

Almost every one complained they can’t add a particular conference room to a meeting request in Outlook. They said the meeting room disappears from their meeting request. Strange, huh! When I checked it myself, sure the resource is added and after a second it did disappeared or removed automatically. Without boring details of analysis, I … Continue reading Exchange: Meeting room disappears after adding to the meeting request in Outlook →

What if you have an email address, you want to know which object that email address belongs to? Mailbox or Distribution Group or Contact or Public Folder? You have to keep searching by the following commands till you find your object. Open PowerShell and connect to Exchange (or Exchange Online). Get-Mailbox | %{$_.EmailAddresses | ?{$_ … Continue reading Exchange: How to search by an email address? →