This is not a developer question, but here it goes:
When you export a property in a schedule to Excel, there is a hidden column with the internal Property ID.
When you delete the Property, it is gone together with the ID.
When you re-import the schedule, ARCHICAD cannot map this property to something that doesn't exist anymore.
If you try to re-create the property, it'll have a different internal ID. So it is lost forever.
You may be able to export your properties to XML, edit the XML to re-enter the old guid and re-import the properties from the XML to re-create the same guid.
--- stefan boeykens --- bim-expert-architect-engineer-musician ---
Archicad28/Revit2024/Rhino8/Solibri/Zoom
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