I load a random number of csv files into Excel anywhere from 10 to 50

Excel shows that each csv file is loaded as a different workbook. each
workbook only has one worksheet

I want to execute a sub on each workbook and then write the created sheet and
close the workbook and repeat for the next workbook until I process all loaded
workbooks

The below macro does that but when all the workbooks are processed the while
loop will not end an trys to execute the subroutines on a blank no workbook
screen

How can I get the macro to stop when all the workbooks have been processed?

Thanks for any help.

Dennis

Sub xTBVarItemMxMnBtALL()

'====================================
' 05/26/2007
'Executes the below subs for each loaded workbook
'Sub xTopBotVarITemMxMnBoot()
'Sub WriteSheetandclose()
'===================================
On Error Resume Next
Dim curwk As Worksheet
Dim curwkbk As Workbook

Set curwkbk = ActiveWorkbook
While curwkbk < Null
Call xTopBotVarITemMxMnBoot
Call WriteSheetandClose
Set curwkbk = ActiveWorkbook
Wend
End Sub