I am navigated to the INTRO instead of the page I want

I am new in ASP.NET and generally in ASP. In a page I created recently there is a Hyperlink WebForm control (tried with Image button as well), displaying a jpg image, which navigates to "http://www.ergose.gr/ergosesite/inner.asp?CONTAINERID=3&REFCI=101&LANGUAGE=1" I noticed that the first time in each session that I click this control I am navigated to the INTRO page of this site "http://www.ergose.gr/ergosesite/intro.asp?CONTAINERID=2&LANGUAGE=1&REFCI=0" In subsequent clicks it works ok. Does anyone have an idea what is happening? Thanks