Windows 10 crash - 4k Video Downloader

I have problem with 4k Video Downloader using Windows 10. It crashs and i can't end the process using task manager of windows. Say to me "access denied". I tried end the process using other programs, like sysinternats, proccess explorer, lock hunter and many others. Every time when this happens, i have to restart the computer to be able to open the program again. I tried desinstall, change the default path of installation. Erased the registry settings too but the problem still happens. The program is becoming unusable because it is crashing a lot and I'm losing a lot of time.