I have modified the Share Application Page and the corresponding code behind. On some machines this works fine, 100% of the time. On some other machines it works for a while and then stops working, on other machines it takes two, three, four or more clicks on the Submit button for the click to be actioned. Does anyone know what the problem is ? or how I can goes about debugging the problem ? I have a debug statement right at the start of my method which logs a message to a log file to say the the button click has resulted in my code being entered. When the button click is not working I get no statements in the log file saying my method has been entered. I am using OnClick= MyMethod() in the buttom statement on the Share Application Page.