When an application layer creates or modifies files they are stored in the writeable sublayer. If the layer is then reset, the files in the writeable sublayer are deleted. This behavior lets you reset an application to the default state if settings become corrupted. However, many applications create data files that you do not want to lose when a layer is reset. These files need to be stored on the base file system and not in the layer to prevent potential loss.
For example, you create and activate a Microsoft Word layer. You do not create any layer exclude entries, global exclude entries, or data layers to redirect .doc files from the layer's writeable sublayer. You then activate the Microsoft Word layer and use it to create .doc files that you save on the computer's hard drive. If you then reset the Word layer, all of the .doc files you created are lost.
To prevent the loss of application data when a layer is reset, you must ensure that the data is not stored in the application layer.
The Workspace Virtualization Agent provides the following methods that you can use to prevent the loss of application data:
Table: Methods to prevent data loss
You can create a data layer that captures the application data files that have specified extensions or that are in a specified directory. A data layer captures the application data so that it is not redirected to the writeable sublayer of the application layer.
Layer exclude entry
You can create layer exclude entries for an application layer. A layer exclude entry can be a file extension or a directory. Application data that matches the layer exclude entry is saved in the base file system.
You can create global exclude entries for a computer. A global exclude entry can be a file extension or a directory. A global exclude entry applies to all layers on a computer. Application data that matches the global exclude entry is saved in the base file system.