>>>but I'm not sure what should I do with this to show me the actual problem with the form.
>>
>>Nothing you can do with it. You need to find where and why it's been called. I asked earlier (somewhere) - do you have the ability to debug on the server? If not then you've not much chance of discovering the problem....
>
>I have a full access to the server where the pages are stored. But how exactly am I supposed to debug them?

If you have VS on the server use that. Simplest way is to hard code a break in the server code handling the postback ('System.Diagnostics.Debugger.Break()' in C#, just 'STOP' in VB). Of course it's better to do this on a development server rather than the production machine <g>