White screen during Windows 7 installation via Bootcamp assistant

Hello everyone.

Macbook pro mid 2012 High Sierra.

I had Windows 7 on my second hard drive (installed in main bay and my MacOS on SDD optical bay), I deleted it via disk utility and decided to reinstall it.

I followed all the steps in bootcamp assistant, after partitioning my hard drive Mac restarted and freezed on white screen.

I had this issue back in the days when I was installing Win7 but I do not remember how I managed to solve this white screen issue. I'm not sure but I pressed some combination and win7 started to install.