The Tech Journal

When attempting to install a Microsoft Exchange Cumulative Update, the readiness checker may fail and stop you from proceeding with the upgrade and installation.

You will be presented with the following error, or one similar:

There is a pending reboot from a previous installation of a Windows Server role or feature. Please restart the computer and then run Setup again.

After restarting the server, and re-attempting to install the Exchange CU, it will continue to present this and stop you from proceeding with the installation.

The Problem

There’s a few different things that can cause this. I experienced this issue when trying to upgrade Exchange 2016 CU18 to Exchange 2016 CU20. This issue can also happen when upgrading from Microsoft Exchange 2019 CU versions, as well as earlier versions of Exchange 2013.

I found a few posts online referencing to delete two registry keys, “UpdateExeVolatile” and “PendingFileRenameOperations”, however these didn’t exist for me.

The Fix

I figured I’d try to install a feature, specifically something small that I may or may not ever use, to see if it would work and to see if it would clear whatever flag had been set for the pending restart.

First, I left the Exchange CU installer window open on the prerequisite check, opened the Server Manager and installed the TFTP Client. After finishing, I hit retry and it continued to fail.

I restarted the server, ran the CU installer again which got stuck on the pending restart. This time I closed the Exchange CU upgrade, installed the “Telnet Client” feature, opened the CU upgrade again, and it finally worked and proceeded!

So with the above in mind, to bypass this issue you must:

1. Restart Server
2. Launch Exchange CU Installer
3. Wait for readiness check to fail (warning of a pending reboot), close installer
4. Install a feature with the Server Manager, such as “TFTP Client” or “Telnet Client”
5. Open Exchange CU Installer
6. Install Microsoft Exchange Cumulative Update successfully!

Hope this helps! Leave a comment and let me know if it worked for you!

Today I wanted to do a brief post addressing Microsoft Exchange Backup and Disaster Recovery.

In the past week I’ve had over 30 people reach out to me via chat looking for help and advice in situations where:

• A Cumulative Update Failed
• Exchange Services will not start
• Hardware Failure Occurred

In all of these cases the admins took a snapshot of their Exchange virtual machine (in Hyper-V or ESXi/VMware), and then restored it to the previous point when the failure occurred. This completely broke their Exchange install and possibly made it unrecoverable.

The above example is what you DO NOT want to do.

Microsoft Exchange Aware Backups

As per: https://docs.microsoft.com/en-us/exchange/high-availability/disaster-recovery/disaster-recovery?view=exchserver-2019

Exchange Server supports only Exchange-aware, VSS-based backups. Exchange Server includes a plug-in for Windows Server Backup that enables you to make and restore VSS-based backups of Exchange data. To back up and restore Exchange Server, you must use an Exchange-aware application that supports the VSS writer for Exchange Server, such as Windows Server Backup (with the VSS plug-in), Microsoft System Center 2012 – Data Protection Manager, or a third-party Exchange-aware VSS-based application.

You must use an Exchange-aware backup and/or disaster recovery application/software suite. These applications are aware of Exchange and designed to perform proper backups of Exchange, the mailboxes, and configuration. Not only do they backup the mailbox database and the VM running Exchange, but they also backup the system state and configuration of Microsoft Exchange.

Simply performing a VM snapshot is not supported and can break your Exchange installation.

Note that the configuration for Microsoft Exchange is stored inside of Active Directory, and not on the actual Exchange Server. Restoring the Exchange Server to a previous snapshot will cause a configuration synchronization gap between the Active Directory configuration and the mailbox database on the Exchange Server.

Options for Backup

There are plenty of options to perform Microsoft Exchange-aware backups.

If you’re looking for something free and easy, you could use the built-in Windows Server Backup function on Microsoft Windows Server. It’s perfect for special migration and upgrade jobs, homelabs, and small/micro sized businesses.

For larger organizations, I’ve used, setup, implemented, and managed the following backup applications:

• Veeam Backup and Replication
• Veritas Backup Exec

There’s no excuse for not having a backup, especially if you call yourself a professional. You should always have a full working backup, especially before performing any type of maintenance, updates, or upgrades to your environment.

Microsoft Exchange Issues and Failures

Additionally, in the event of an issue, the solution isn’t always to restore from backup.

In most cases when something fails, it’s best practice to troubleshoot and correct the issue, instead of blasting away Exchange and restoring from backups.

Most Exchange installs can be saved simply by following standard troubleshooting procedures. Even if an Exchange Cumulative Update fails, you can fix what caused it to fail, and then re-run the installer/upgrader to attempt to recover! No backup restore needed!