If there are any remote proxies in use:
During .msp install, the default proxy is updated automatically. But if there are any remote proxies in the environment, use the procedure below to upgrade them.
1. When .msp is installed, run Veeam Backup for Microsoft Office 365 application, go to Backup Infrastructure, right-click on the Backup Proxies and select Upgrade.
2. In the wizard choose the remote proxies that should be upgraded.
3. When the upgrade is done, the upgrade statistics will be shown.
4. Confirm the backup from the remote proxies can be browsed.