Upgrading an HMS Installation


The Hurricane MTA Server (HMS), starting with version 2.0, requires one or more pre-installation actions before either performing a new installation or when upgrading from a 1.x installation. These requirements vary based on the version of Windows Server being used, so please see our HMS System Requirements for more information. Please ensure that you have met all prerequisites for a new HMS version before performing the upgrade.


The installers for the MTA referenced in this document can be found at the following locations, based on the major version:

Version 1.x

Version 2.x

Version 3.x

📘If you are upgrading to Hurricane MTA 3.X+

Please see our specific Hurricane MTA Server 3.0 Upgrade Guide.


Before proceeding, if you are upgrading from an HMS version prior to on a 64-bit system, please also read the 32-bit to 64-bit Upgrade section below.

Upgrades can be performed in one of two ways:

  • Download the latest installer from our website, from the appropriate location specified in the HMS Installers section of this document. When running an installer, please save it to the local system before execution instead of running it directly from the download in the browser.
  • If the currently-installed version is 2.0 or greater, there is an Update or Uninstall shortcut under the Hurricane MTA Server start menu group.

All settings are preserved during an MTA installation, even when upgrading from 1.x to 2.x or 2.x to 3.x. We strongly recommend backing up your HMS installation before running any upgrade. This can be done by simply zipping up the HMS installation directory, which should be named Hurricane MTA Server. Backups should only be created while the HMS services are all offline. Once a backup is made, running the installer upgrades the MTA in place. Please note that it is not possible to have multiple HMS installations on a single system.


It is important to note that as of MTA versions 2.1 and above, we preserve all web.config files in the MTA's service directories such as "www". We also install the latest web.config generated by our services and place it in those folders with "new" prepended to the file name. This allows existing web.config settings to be preserved during an upgrade or reinstallation, while still providing a newer version of those settings. You may wish to or need to integrate settings from the new web.config with the existing version. If errors related to web.config settings are encountered the first time the Control Panel or another web service is brought online after an upgrade, the web.config settings are a likely culprit and should be investigated before checking for other issues.


In the special case of upgrading a 32-bit HMS installation to a 64-bit installation, additional concerns should be addressed. This process only applies to versions of the MTA prior to installed on 64-bit systems. When upgrading the MTA in this scenario, the installation process will force the MTA installation to become 64-bit.

The following should also be noted:

  • Create a backup of your current HMS installation prior to upgrading.
  • Before upgrading, ensure that any MTA plugins in use by the MTA are 64-bit compatible or else they could fail post-upgrade.
  • It is not recommended or supported to downgrade to a 32-bit installation after the 64-bit upgrade has completed. Please consider such an operation irreversible and plan appropriately.
  • A 32-bit MTA installation will have installed into the Program Files (x86) folder by default. An upgrade from 32-bit to 64-bit will not change this.
  • During the upgrade process, the embedded database master.fdb is also upgraded. This process requires the data to be duplicated, and the original database is left in place. You will want to ensure that a system has enough disk space prior to an upgrade, and the original database can be archived and deleted manually once the upgrade is complete.
  • When upgrading, the size of the master.fdb embedded database can significantly affect how long the upgrade process takes. Please be patient if you have a large database and do not cancel the upgrade prematurely.

In the case of a faulty or unwanted upgrade, it is possible to revert to a previous version.

In the case of reverting from a 2.x installation to a 1.x installation, the safest method is to re-run the 1.x HMS installer, which will preserve the settings and data but replace the MTA with the 1.x version.  Be warned that running the 1.x installer could potentially install a newer version of 1.x than existed before the original 1.x to 2.x upgrade. If this is the case, you will need to restore your HMS installation using a self-made backup as described in the Upgrade Process section above. In this scenario, care should be taken as backups contain the exact state of messages, queues, and account settings. This means that if any processing was performed since the backup was taken, messages could be duplicated or lost and settings could change.

If you find yourself in a downgrade situation too complex to be resolved by the procedures described in this document, please email support@socketlabs.com and we will assist you with this process.