IIS 7 settings for directories without / at the end

Question

i searched here, but i didn't find the solution to my problem

So, basically, this is what i want. I moved a website to a server that has IIS 7 installed, and now when i put in the address bar a link like: domain.com/folder , it gives me a 404 error.

folder is a directory that has inside a default.aspx file. but if i put domain.com/folder/ , it works. So i guess it's an IIS setting.

so, the question is what should i do to make this work? so it's not about not having a default file set, like others recommended me. it has the default.aspx and it works if i put the slash at the end. so i guess IIS considers that if it doesn't have a slash, it's a file. well, it's not, and i guess it must be a setting for that