When you run into this error in your ASP page:

A trappable error (C0000005) occurred in an external object. The script cannot continue running.

Not every time, but in most cases that I have seen this, it generally means that in your form that you are submitting, you have a input item that does not have a name.

<INPUT TYPE="Button" VALUE="Test">
Look through your code for any INPUT fields that do not have a NAME='something' and give it a NAME value like:

<INPUT TYPE="Button" NAME="Submit" VALUE="Test">
NOTE: I just used the TYPE="Button" as an example. It could be any INPUT TYPE.