I'm using the following function:

Function ReadCell(msheet, mCell)
'ReadCell = ActiveWorkbook.Worksheets(msheet).Range(mCell).Val ue
ReadCell = Workbooks("this.xls").Worksheets(msheet).Range(mCe ll).Value
End Function

The remmed out line caused a problem when two instances of Excel were
open at the same time, and the replacement line referencing the
absolute xls filename fixed this.

However, if the filename isn't "this.xls" it fails. Excel knows the
filename somehow, as it's used as the main Caption. Can I get at this
somehow and use it instead?

Thanks - Kirk