capcha = 0
On Error Resume Next
captcha = CINT(Request.Form("year"))
On Error GoTo 0
If captcha <> Year(Date) Then
will be a *NUMBER* so you want to ensure that what comes from the user is also a number.
The ON ERROR code allows you to force the value from the <form> posting to be a number. If it is not, then captcha
will remain at 0 and of course not match the year of today's date.