Error "Object reference not set to an instance of an object"

[elsekra]

Hello !
I am using QTP 9.2 with .Net Addin and Test Advantage 2006 V3 CLR x2
When i execute the following line :

Code:

SwfWindow("R2D2 - Result Reconciliation").SwfWindow("Ecran Détails").SwfTable("ultraGrid1").GetNAProperty("Rows[0].Cells[0].Column.Key")

an error pop-up appair with message "Object reference not set to an instance of an object". The code is correct i think , but i dont know why it block wan i use the .GetNAProperty Methode. If someone can help[/align]
Thx