From Forum Nokia Wiki

Applications installed on S60 3rd edition devices are not backed up (during device's back-up) by default. In order for an application to be backed up and later restored the following has to be done:

1) create a file named backup_registration.xml, with the following content:

<?xml version="1.0" standalone="yes"?>
<backup_registration>
  <system_backup/>
</backup_registration>

2) include this file in project's pkg file, so that it is installed in application's own private folder

"backup_registration.xml" - "!:\private\<UID>\backup_registration.xml"

where <UID> is the UID of the installed application Note: more information about private folders and data caging can be found here: Data caging

 3) Note that you also need to add an additional piece of XML like this to backup_registration.xml if you want to back up any files installed by your SIS file to the \private\ folder:

<passive_backup>
  <include_directory name="\" >
</passive_backup>

Otherwise you will end up with an incompletely restored installation.

More details can be found in this tutorial on NewLC or in TSS000750 - Enabling backup and restore for installed C++ applications.

Related articles

TSS001073 - Backup of add-on DLLs