Purpose
It is important to remember that Veeam Backup for Microsoft 365 and Veeam Backup & Replication are separate backup products designed to operate separately from each other. However, both Veeam Backup for Microsoft 365 and Veeam Backup & Replication utilize Veeam Explorers as secondary applications to perform application item restores. The Veeam Explorers are installed alongside either backup application. Due to this shared use of the Veeam Explorer applications, it is imperative that when both Veeam Backup for Microsoft 365 and Veeam Backup & Replication are installed on the same server, that only specific compatible versions be installed (see table below). Failure to ensure compatibility could lead to a situation where one backup product may not be able to utilize the Veeam Explorer application installed by the other backup product, thus causing application item restores to fail.
Solution
When installing Veeam Backup & Replication (VBR) and Veeam Backup for Microsoft 365 (VB365) on the same server, be mindful of the following compatibility when upgrading.
Note: As new versions of either product are released, they will be added to the table, and as versions reach End of Support, they will be removed. The release schedule of these products is not synchronized. If a version of either product is released before the compatible version of the other, it is critical to wait until inter-compatible versions are available. For example, if a new version of Veeam Backup & Replication is released and a compatible version of Veeam Backup for Microsoft 365 is not available yet, upgrading Veeam Backup & Replication would lead to the issue documented in KB3028.
