Invalid string or buffer length

I know I've seen this error before .. I can't remember how I solved it and
it's 3 AM and I have a 9AM deadline.

I am using Access 2003 .. I have a form with about 40 fields and this is an
Insert Record statement. The fields are large enough to accommodate the
info of each field and I am testing with localhost using IIS5.1 I think it
is or whatever comes with XP Pro.

Could the buffer length thing be something to do with the total amount of
information? Method of sending? An IIS setting?

Any replies greatly appreciated.

Nancy