Installation and Upgrade > Upgrade Guide > The Windchill Upgrade Procedure > Setting Up the Target System for Upgrade > Configuring Your Series for Upgrade
  
Configuring Your Series for Upgrade
To configure your series for upgrade, perform the following:
1. Verify that the wt.series.* properties in your <Windchill>\codebase\wt.properties are in sync with the source system’s wt.properties file.
Keep the following in mind:
Any changes must be made in the site.xconf file and propagated to this file.
If you wish to make a change to the target system’s series, the change must be done post-upgrade.
2. If your source system has file-based series, then you need to verify that the file-based series on the target system is in sync with the source system’s file-based series. Ensure that the versioning scheme is set up in wt.properties on the target system exactly like it is on the source system.
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If you wish to make a change to the target system’s file-based series it must be done post-upgrade.
3. If your source system has customized series that are not wt.properties based, then you need do one of the following:
Move the custom series to a file-based series before upgrade. Remove any customizations. PTC highly recommends this to avoid upgrade issues.
If the file-based series is not available on your source system, then the customizations will need to be ported to the target system before upgrade. Post-upgrade, you should move the custom series to a file-based series and remove the customizations.
4. Verify that there are object initialization rules (OIRs) for every versioned object type in the system and that they are using a valid series (defined in wt.properties or a file-based series). Ensure that the wt.properties has the same series configuration as the source system.