The device goes back to the backup tested update, which is always stored on the device as a backup.
Introducing new device models Make available all software updates relevant to a new model of an IP phone that is being introduced to the market.
You can also use Device Update Web service to roll back devices to previous software versions.
We recommend that you check for updates every three months.
Microsoft makes updates available in cabinet (files) that you can download from the Microsoft Help and Support website.
Microsoft Lync Server 2010 includes the Device Update Web service, which is automatically installed with Web Services.
You can use this service to download updates from Microsoft, test them, and then deploy the updates to all the IP phones in your organization.
An update file contains updates for one or more unified communications (UC) devices.
After obtaining the file, you upload it to Device Update Web service by using the Lync Server Management Shell.
You will need to check every Front End Server in the pool, as the user’s logs could have been updated to any one of them (the routing algorithm determines this based on load).