VBA xlPasteValues fails on 2nd run - excel

Question

I have a short code that basically copies a selected row to another sheet, and deletes it from the first.
For some reason when I run this, it will run just fine, if I then select a different row, I get a pasteSpecial method of RangeClass failed error.
Sub Completed()
Dim trackerRow As Integer, compRow As Integer, answer As Integer
Application.ScreenUpdating = False
Application.CutCopyMode = False
trackerRow = ActiveCell.Row
compRow = Sheets("Completed").Cells(Rows.Count, "B").End(xlUp).Row
If trackerRow < 3 Then Exit Sub
If Cells(trackerRow, 2) = "" Then
MsgBox "This row is empty, please select the candidate you want to move.", vbExclamation, "Empty Row"
Else
answer = MsgBox("Are you sure you want to move " & Cells(trackerRow, 3).Value & "?", vbYesNo, "Confirm move?")
If answer = vbYes Then
'move row
Rows(trackerRow).EntireRow.Copy
With ThisWorkbook
With .Sheets("Completed")
.Activate
.Unprotect "HSBC2017"
.Cells(compRow + 1, 1).PasteSpecial xlPasteValues '**error line**.
.Protect "HSBC2017"
End With
With .Sheets("Tracker")
.Unprotect "HSBC2017"
.Rows(trackerRow).EntireRow.Delete
.Protect "HSBC2017"
.Activate
End With
End With
End If
End If
Application.ScreenUpdating = True
Application.CutCopyMode = False
End Sub
I can't work out why when I open the document it will work once, but you have to re-open to run a second time?

Answer 1

Each time you crash into a debug, you leave the destination Completed worksheet unprotected. Closing the workbook and reopening it leaves it unprotected.
Unprotecting an unprotected worksheet does not cancel the .CutCopyMode but unprotecting a protected worksheet does.
So in the first run-through with an unprotected destination worksheet there is something on the clipboard (and you have 'dancing ants' on the row-to-copy on the Tracker worksheet). Since everything runs through, the destination Completed worksheet is now protected and a second run-through will cancel the .CutCopyMode when the worksheet is unprotected. You can watch this by stepping through your code with F8 and see the 'dancing ants' disappear from the copy area on the Tracker worksheet as soon as you unprotect the Completed worksheet a second time.
Possible solutions (with a nod to comments from Peh and Rory):
Protect the worksheet with a password and UserInterfaceOnly.
with worksheets("Completed")
.Protect Password:="HSBC2017", UserInterfaceOnly:=True
end with
This only has to be done once and you can remove both the .Unprotect and .Protect code from future sub procedure operations. Only actions made manually by the user will be restricted.
Initiate the copy from the source worksheet after unprotecting the destination worksheet.
with worksheets("Completed")
.Unprotect Password:="HSBC2017"
worksheets("Tracker").Rows(trackerRow).EntireRow.Copy
.Cells(compRow + 1, 1).PasteSpecial xlPasteValues
.Protect Password:="HSBC2017"
end with