Loading IT Shop is slow

Hi community.

I'm wondering why loading IT shop in a web browser is so slow? It tooks more than a minute or two to show the login page? Do I have to set anything in configuration, maybe on IIS? Server where IT shop is runnig is virualized, has two processors and 4 GB of ram.

Please let me know if you have any idea or best practise how to configure IT-shop in IIS?

Thanks,

Evgen