This topic describes considerations for installing hotfixes.

It is imperative that the normal day-to-day operation of your business is not disrupted when installing hotfixes. Consider the following general guidelines when evaluating hotfixes or changes to the installed Microsoft Dynamics AX implementation.

See the Microsoft Service Management Functions Operations Framework Guidefor information about defining processes, establishing best practices, and managing IT solutions.

Evaluate the hotfix

Each hotfix is created to address a specific issue, problem, or customer scenario. Distribution of hotfixes is limited to those customers, partners, and organizations that can benefit from the changes made to the code, based on analysis from Microsoft technical support personnel. Each hotfix is released with documentation indicating what files, tables, code, or functions are changed by the hotfix.

Prior to installation, review the knowledge base (KB) article released with the hotfix to determine applicability and impact of the hotfix on your environment.

Note Note

If you customized your environment before you received a hotfix, thoroughly review the KB article that documents the hotfix. Any objects that are affected by the hotfix will need to be investigated. The investigation needs to determine if the changes implemented by the hotfix should be merged with customizations in a higher layer such as BUS, VAR, USR, or CUS.

Test the hotfix in a test environment

Once the decision has been made to install the hotfix, it should be installed in a test or backup environment and validated against the implementation, customizations, data, and processes currently in place in your organization.

Due to the unique architecture of Microsoft Dynamics AX implementations, there are many possible issues that can be encountered when installing a small code fix or change. All business scenarios and customizations should be tested to verify that the hotfix is behaving as expected, that it is not impacting other areas, and that the resulting data is correct.

Install the hotfix

Installation of a hotfix should be done according to the instructions in the associated KB article. Take care, as well, that business processes or operations can be restored to their original state in case of problems with the installation.

  • Back up the database and application files being updated. Backing up the affected files will allow you to rollback to a known, reliable version if necessary. Proper backup and the ability to revert back to a previous version will help reduce downtime in case of an unexpected error.

  • To ease comparisons between the previous SYP layer and the new version after installing the hotfix, copy the SYP layer as instructed in the KB article.

  • Schedule a time when the fewest system users, or no users, will be affected. Announce the time in advance to make sure users are aware of the pending update and expected downtime. A best practice is to notify all users of the update time to minimize data loss, data corruption, or loss of productivity.

  • Make sure the system is in a single-user mode during the hotfix installation with only the administrator designated to do the update. Changes to the code can affect the Application Object Server (AOS) and therefore affect users currently on the system.

    Caution note Caution

    Changes to the application may require a compilation or synchronization of the application. These operations will add to downtime.

Validate the hotfix in test and production environments

After the successful installation of the hotfix, check the install log to make sure there are no error messages and warnings that can impact the operation of the system. Test the system to make sure that:

  • The change implemented by the hotfix is working as expected.

  • The change has not impacted other areas of the system.

  • The Microsoft Dynamics AX application as a whole is working as expected.


In the event that there are errors or issues with the installation of a hotfix, the hotfix needs to be uninstalled and the system needs to be rolled back. You can use the following steps to restore your system to the last known, good version:

  1. If the hotfix installed any binary files, uninstall the hotfix by using the Control Panel > Add/Remove Programsoption.

  2. Restore the application directory and database backups.

  3. Synchronize the application with the database, if required, to return the implementation to pre-update conditions.

  4. Optional: For assistance with troubleshooting the installation errors or issues, open a support request by contacting your partner or value added reseller (VAR), or, if enrolled in a support plan directly with Microsoft, you can log on to CustomerSource and submit a new support request.