I have Asus all-in-one PT 2001 computer and I turned on but just black screen, I just seen the mouse icon. What should I do?

I have ASUS all-in-one PT 2001 computer and I turned on but just black screen, I just seen the mouse icon. What should I do?
Before never was any problem with my computer. I used about 2 years ago.
 
It could be that Windows OS is updating, so just leave it on for 6-8 hours.

All-in-One is similar to laptop as the components are integrated, so take a look at these articles: https://www.techadvisor.co.uk/how-to/windows/how-fix-black-screen-in-windows-10-3682969/ https://www.computerhope.com/issues/ch001319.htm
Thank you so much for your help!
Everything is perfect after 6-8 hours.
You were right and very helpful!
Thank you again and Happy Holidays and Merry Christmas.
 
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