cant open or refresh data module

[BORUCH]

hi

i'm getting an error when opening my power piviot data module
cant open the data module because there was a com exception while opening


Error Message:
============================


Attempted to read or write protected memory. This is often an indication that other memory is corrupt.


============================
Call Stack:
============================


at Microsoft.Office.Interop.Excel.WorkbookClass.get_Connections()
at Microsoft.Office.PowerPivot.ExcelAddIn.EntryPoint.EmbeddedConnectionLookup(Workbook wb, WorkbookConnection& conn)
at Microsoft.Office.PowerPivot.ExcelAddIn.SandboxVersionManager.IsUpgradeNeeded(Workbook workbook)
at Microsoft.Office.PowerPivot.ExcelAddIn.InProcServer.LoadOLEDBConnection(Boolean raiseCompleteEvent, String errorCache)


============================

how can i solve this issue?