posmarketing Hi. I'm afraid this is not an answer to my question. I read all thread again and there was no mentioning about what I've just about.
Please read my last post one more time. I've found out what is the problem, (index.php added to links when it's not needed), I've checked the code of our module and no "index.php" is being added. Instead links are created with joomla function JRoute, so this problematic part of the url must be added by some 3rd party extension or customizations.
In summary. I've asked if You have installed any extensions/plugins before noticing this issue and/or if there were any customizations. It will help me to narrow down the places to look for a cause of it. I've also asked to update Joomla to latest version since it can be a problem coming from it directly.
And finally, can You put the testing page I've created back? As said it is not connected to any page, so none of the visitors of Your site would ever go to that page.