Userform object not recognized

[aroush]

I've created a wizard that steps through 5 userforms as the user clicks "Next" command button. The only code that I've put in this is as follows:

Private Sub cbNext1_Click()
Unload Me
RFQSetup2.Show
End Sub

This has worked in many of my files but for some reason it has stopped working. I recently added code from other files for worksheet protection and unprotection. When I click the Next button now I get error:

Run-time error '424'
Object required

I have know idea why because the userform2 name and properties have not changed. Please help.