You can edit a custom property that you have update rights to.
Do the following:
Open the QMC: https://<QPS server name>/qmc
Select Custom properties on the QMC start page or from the StartS drop-down menu to display the overview.
Select one custom property and click Edit in the action bar at the bottom of the page.
Edit the properties.
Property Description Name The custom property name is mandatory and must not be empty. The value must only use characters and numbers (A-Z and 0-9) and must begin with a character (A-Z). Description Optional. Add a description of the custom property. Property Description Resource types
Select the resources that you want to make the custom property available for.
Custom properties can be applied to the following resources:
User synchronization tasks
The values that you create can be used in security rules.
Click P Create new in the Values heading; type the value and click OK to add the value.Note: The value must be applied to a resource before it can be used in security rules.
Click E to delete a value from the Values list and click OK to confirm.
Click Apply in the action bar.
Successfully updated is displayed at the bottom of the page.