I promise I have searched thoroughly for an answer before posting...I'm not that lazy...
And I have many hours invested in trying to resolve this on my own...but obviously my skills are limited our I wouldn't be supplicating to the gods of Excel in this forum (I have solved many a prior issue reading solutions here...).

I am copying the content of a cell in one workbook to another. I iterate through the rows by each column needed to copy the source then paste in the target.

I test that the source row contains data with CStr in the first column. It works about 900 times then suddenly stops (at the same point every time).

The source sheet has 41 rows. I can't copy the whole rows because there isn't a direct mapping to the target sheet. I need specific columns in the source and to paste to specific columns in the target. The rows do match 1 for 1 however.

I have a separate macro for each column needed because I am too simple to use variable appropriately. Below is an example of the macro that fails. The code is identical for each macro and is called by a master macro. the macro below passes the While test 12 times then fails (even though row 13 has data). Among the set of macros pasting to the target sheet, the While tests true about 900 times, and the fact that is tests true 12 times then fails in the questionable macro is really surprising to me.

Sub itdDM_BID()

Dim LSearchRow As Integer
Dim LPasteRow As Integer
Dim LSearchCol As String
Dim LPasteCol As String
Dim myWB As Workbook
Dim tWb As Workbook

'The script is specific to the Workbooks being used and the Workbooks must be open!

Set myWB = Workbooks("Data Modeling Tasks.xlsm")
Set tWb = ThisWorkbook

'Specific to "Data Modeling Tasks"

'Reset the row and column variables

LSearchRow = 2
LSearchCol = "J"
LPasteRow = 2
LPasteCol = "A"

'Loop to copy "Data Modeling Tasks" BID column text to column "A" in master (ThisWorkbook) row by row

    While Len(myWB.Worksheets("Sheet1").Range(LSearchCol & CStr(LSearchRow)).Value) > 0
        
       myWB.Worksheets("Sheet1").Range(LSearchCol & LSearchRow).Copy
       tWb.Worksheets("Sheet1").Range(LPasteCol & LPasteRow).PasteSpecial (xlPasteValuesAndNumberFormats)
        
       LSearchRow = (LSearchRow + 1)
       LPasteRow = (LPasteRow + 1)
       

    Wend

End Sub
I wouldn't be so spooked if the loop the While statment didn't work at all, but the fact that it *stops* working seems very strange.... And that row 13 test true for every other macro using the same loop (just with different column variables) seems even weirder...

Thanks in advance for any help.

John