Hi John

yes that was just a typo before.
I've copied my code below the message I get is
Method Unprotect of object worksheet failed.
txtOld is the old password entered into a textbox on the
form.

Private Sub cmdChange_Click()
If MsgBox("Changing passwords will result in the current
data being lost" & vbNewLine & _
vbNewLine & "Do you want to continue?", vbYesNo) = vbYes
Then
Sheet1.unprotect PASSWORD:=Sheet3.Range("H65536").End
(xlUp).Value
ThisWorkbook.unprotect PASSWORD:=Sheet3.Range("E65536").End
(xlUp).Value
If optMan = True Then 'manager authorisation password
Select Case txtOld.Text
Case Sheet3.Range("b65536").End(xlUp).Value
If TextBox1.Text < TextBox2.Text Then
MsgBox "Passwords are not the same!" & vbNewLine
& "Please try again", vbCritical
TextBox1 = ""
TextBox2 = ""
TextBox1.SetFocus
Else
Sheet3.Range("b65536").End(xlUp).Value =
TextBox1.Text
Call save
End If
Case Else
MsgBox "Invalid Password", vbCritical
txtOld = ""
txtOld.SetFocus
End Select

ElseIf optWB = True Then 'workbook password
Select Case txtOld.Text
Case Sheet3.Range("e65536").End(xlUp).Value
If TextBox1.Text < TextBox2.Text Then
MsgBox "Passwords are not the same!" & vbNewLine
& "Please try again", vbCritical
TextBox1 = ""
TextBox2 = ""
TextBox1.SetFocus
Else
Sheet3.Range("e65536").End(xlUp).Value =
TextBox1.Text
Call save
End If
Case Else
MsgBox "Invalid Password", vbCritical
txtOld = ""
txtOld.SetFocus
End Select

ElseIf optWS = True Then
Select Case txtOld.Text
Case Sheet3.Range("h65536").End(xlUp).Value
If TextBox1.Text < TextBox2.Text Then
MsgBox "Passwords are not the same!" & vbNewLine
& "Please try again", vbCritical
TextBox1 = ""
TextBox2 = ""
TextBox1.SetFocus
Else
Sheet1.unprotect PASSWORD:=txtOld.Text
Sheet3.Range("h65536").End(xlUp).Value =
TextBox1.Text
Call save
Unload Me
End If
Case Else
MsgBox "Invalid Password", vbCritical
txtOld = ""
txtOld.SetFocus
End Select

End If
End If
End Sub

Sub save()
With Sheet1
.Range
("C16,D2:F2,D6:F6,D8:F8,D18:G21,F24:F28").ClearCon tents
.TextBox1.Enabled = True
.TextBox2.Enabled = True
.txtSpecify.Enabled = True
.TextBox1 = ""
.TextBox2 = ""
.txtSpecify = ""
.TextBox1.Enabled = False
.TextBox2.Enabled = False
.txtSpecify.Enabled = False
.cmdChange.Enabled = False
.CommandButton1.BackColor = vbRed
.CommandButton1.Caption = "Ï"
End With

ThisWorkbook.save
ThisWorkbook.Protect PASSWORD:=Sheet3.Range("e65536").End
(xlUp).Value, structu=True
Sheet1.Protect PASSWORD:=Sheet3.Range("h65536").End
(xlUp).Value, USERINTERFACEONLY:=True
End Sub