Let's have a conversation - I Need Help ASAP

I developed a web application using ASP.NET (C#) and am having an issue I can't point the cause. The site drives automatically using timers and its like a display/response type site. After a simple login, you are presented with a question for a finite time, then you are given another finite time to give your answer. This cycle repeats for certain amount of questions, then you go to a status page like type. Then the entire process repeats.

The issue arise when while going through these questions and response cycle, the web suddenly exits the cycle and presents the login page. Nothing is being caught through any exception calls, as nothing is written to my log file. I don't get any http error either. It goes straight to another page without warning. (the default.aspx is not being used, as the login.aspx is of own creation) I think it goes to this page, because its the "defaultDocument" as configured in the config file. This seems to happen sometime during when the site should display the question, or when a response should be given.

I have a feeling it has something to do with my timers (and/or AJAX) since it happens when one of my timers is supposed to execute (or it happens right after timer event happens). I need some major help with this, so if you are reading, just tell me what you think it is. I'll run down your idea. I don't have a firm grip on .net framework and the underlying workings of what my elements/events are doing, as I learn from trying things out. Hopefully, the way I coded things didn't bite me in the end. (thinking now it could be some type of thread issue?)

I"m blaming the issue on a .NET that's why it's here. While my application does interact with a database, I don't believe it's a database issue. Any other suggests and help???