It is possible to create a single Task Sequence that can be used to execute both New Computer and Computer Refresh (aka Wipe and load) scenarios, using logic within the Task Sequence that executes the necessary groups of steps depending on whether the Task Sequence started in the full OS (in which case it would be a Computer Refresh scenario) or started in Windows PE (in which case it would be a New Computer scenario). The same Task Sequence can also restore previously captured data and settings to a new computer.

"Destructive" vs "Non-destructive" Wipe and load

Throughout this documentation (especially relating to the Windows Servicing Assistant) you will find references to "Non-destructive Wipe and load" and "Destructive Wipe and load". Wipe and load is just another name for the Computer Refresh scenario - the disk is wiped and a new operating system image is installed. The Task Sequence always creates a temporary storage folder (_SMSTaskSequence) that is generally preserved through the entire deployment process - the 'wipe' part of the wipe and load process is performed by the Install Operating System Image step and deletes everything on the diskĀ except the _SMSTaskSequence folder. This folder can therefore be used to store content required by the Task Sequence and can also preserve user data when using the User State Migration Tool (USMT) with the file hard link option (links in the file system are created in the _SMSTaskSequence folder for any files to be captured - the original file location can then be 'deleted' from its original location but the file still exists on the disk (linked in the _SMSTaskSequence folder) and can be restored after the disk is wiped. We refer to this scenario - where the Task Sequence does not include any steps that partition or format the disk - as a Non-destructive Wipe and load. Although the original Operating System is wiped, the _SMSTaskSequence folder is not destroyed so can be used to store content and user state.

The exception to this method is when the Task Sequence includes steps that repartition or format the hard disk - in which case any content in the _SMSTaskSequence folder at that point in the Task Sequence is destroyed along with everything else on the disk. We refer to this scenario - where the Task Sequence includes steps that partition or format the disk - as a Destructive Wipe and load. In this scenario we can't store content or user state in the _SMSTaskSequence folder as it will be destroyed. We therefore need the content to be available on a local peer and will also need to store user state on a local peer. Alternatively, when the Windows Servicing Assistant is used, content and user state can be stored on USB media. This is particularly useful when you need to support deployment of a destructive wipe and load task sequence to a remote user that has no peers available.

Generally, the non-destructive wipe and load is preferable as it enables all content to be pre-cached on the PC (using the 1E Nomad pre-caching feature) before the Task Sequence is executed and as USMT uses hard links to preserve user files additional storage is not required for user data and the capture and restore process is generally much quicker. Since the release of Configuration Manager Current Brach 1610 and Windows 10 1703 (with the MBR2GPT tool) it is also possible to convert the device from BIOS to UEFI using a non-destructive wipe and load Task Sequence (i.e. without repartitioning the disk). A destructive wipe and load would still be required if you are switching from 3rd party disk encryption to BitLocker, or if you have any other requirement to repartition the disk.

The following pages provide details on creating the Task Sequences to support the New Computer and Computer Refresh (aka wipe and load) scenarios.