IPN sandbox test results in IPN Delivery Failed:500 Internal Server Error

[mercy]

I am very frustrated right now. I have used the sample code for ASP.NET VB.NET to make a listener page. I test with the sandbox IPN simulator and get the error message. The only thing I did in the page was add code to log the incoming messages. The first incoming message actually makes it. The code for logging comes after the code for sending and receiving replies/responses. it seems to make it through all of this code without an error on my page, and gets to the logging code. it is not an issue with permissions creating/writing to a text log, I am logging into my database. As I said, the first incoming message is logged, but nothing else is logged. I'm very confused. This is PayPal's own code up to the point of the logging. Why is it giving an error like this?The page is not in a protected folder (I have subfolders with roles specified in separate web.config files in the folders), it is in the root where the Default.aspx page is located. My entire site is in secure mode (SSL certificate).Please help!Dana