IsEmpty() Function not evaluating properly

I have tried IsNull and IsEmpty MULTIPLE ways within the following function.  However, it does not evaluate properly because I continually get the same response:  cannot be a zero length string.  Any suggestions as to what I'm missing?  I've assisgned 500 pts b/c extremely urgent that I finish this today.  
fyi:  opbene.value refers to ta textbox in the main form with initial value set to "".

sub addrec()
Dim form1, form2, form3, form4, form5, form6, form7, form8, form9, form10

form1 = main.UWRTR.value
form2 = main.PWD1.value
form3 = main.APPNAM.value
form4 = main.RELSHP.value
form5 = main.DTCODE.value
form6 = main.STATE.value
form7 = main.NOMEMB.value
form8 = main.PLAN.value
form9 = main.DEDAMT.value
form10 = main.OPBENE1.value
       If IsEmpty(form10) Then
         form10 = "NONE"
      Else
        form10 = main.OPBENE1.value
      End If

dim conn, rs, strsql

strsql = "INSERT INTO REFERRALS (UWRTR, REFNO, APPNAME, RELSHP, DTCODED, STATE, NOMEM, PLAN, DEDAMT, OPTBENE1, OPTBENE2, OPTBENE3, OPTBENE4) VALUES ("
strsql = strsql + "'" & form1 & "', '" & form2 & "', '" & form3 & "', '" & form4 & "', '" & form5 & "', '" & form6 & "', '" & form7 & "', '" & form8 & "', '" & form9 & "', '" & form10 & "', '" & form11 & "', '" & form12 & "', '" & form13 & "')"


ALERT(strsql)
Set conn = createobject("adodb.connection")
      conn.open "DRIVER={Microsoft Access Driver (*.mdb)};DBQ=\\server\folder\subfolder\TST.mdb"
   conn.Execute strsql,,129
   conn.Close:  Set conn = Nothing


Alert("Script is finished!")

End Sub


</script>
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