This board is for phpBB support not general programming issues. I didn’t see a board on your site so you will need to supply more information such as a url to your board or find a support site that deals with .net & php conversions.
Searching convert .net to php gets a few hits on Google.
"The good news is hell is just the product of a morbid human imagination.
The bad news is, whatever humans can imagine, they can usually create." - Harmony Cobel