Hello World

User enters data into a form control for the purpose of generating a
manifest. I want to stop the user from entering more than 30 products
within a single userform. The controls are linked to a worksheet called
"Temp". Also on the same userform I want to be able to tell the user if any
information is missing for instance this code executes the msgbox but then
procedes with the rest of the code?

Sub Name()
Sheets("TEMP").Select
If Range("E40") = "-" Then 'Relates to a cell where information is
copied from into. "-" = product code seperator.
MsgBox "You must enter a Product Code!", vbInformation
End If
User_InputP.Show 'Userform for entering products.
'rest of code to copy and paste information into a table

TIA
Mark