SwCustPropMgr   - Run-time error '10'

Hi

Sometimes I get run-time error '10'  'The array is fixed or temporarily locked'    

In the line>          names = swCustPropMgr.GetNames

In the code I loop throw a lot of files, and scan all the properties in each part.

Can anybody help ?

BR Niels

.......          

             Dim names As Variant

.......

            Set swCustPropMgr = swModel.Extension.CustomPropertyManager("")   

            names = swCustPropMgr.GetNames

.......