i cannot understand what is happening, and i need to solve the problem.

the following snippet of code is used six times in the programme

Code:
 ExcelFile.Worksheets("Calculations").Range(CellAdres).Activate
     Clipboard.Clear
     ExcelFile.Worksheets("Calculations").Range(CellAdres).Copy
     WordObj.ActiveDocument.Tables(i).Rows(j).Cells(k).Range.Paste
the programme may run once, or even twice, successfully, but at some time it hangs and advises:

"This method or property is not available because the clipboard is empty or not valid"

using the debugger i know this happens in different parts of the programme, but always in the above snippet.

the curious thing is that it only happens on my desktop in my office, not on my laptop.

can anyone help me please?

john