Windows 7 does not start

[Chuenmon]

My PC : Desktop, Windows 7 Pro. 

There are 3 PCs on my workbench.   One Windows 10 64b. is for processing my photos.  Another Windows 10 64b. is for general uses.  The Windows 7 Pro.  is a backup & occasionally used on the internet.  

In June this year, the Windows 7 was updated again.  Then the PC started having problem on start, did not start sometimes.  I had its network cable unplugged.  It started normally.  This lasted for about a month.  The network cable was plugged back in while the PC was running.  The PC shut itself down a few minutes later.  It does not start since then.

How to eliminate this problem, please?

Thank you.

Chuenmon  

[#2]

What happens when you Power on the system?
Are you seeing the Windows logo?
Are you seeing a Blue Screen error?
Is there any error message?

[#3]

Thank you.
"What happens when you Power on the system?"
Nothing. Simply no power on. Even the start button on the PC case is not lit.

By the way, would you please tell me frankly if I am in a wrong place? I am just a PC user, not of any TECH in anyway.

Thanks.
Chuenmon

[#4]

You might ask your question in Microsoft Answers:
https://answers.microsoft.com/en-us
We answer your question the best we can but Microsoft Answers dedicated to Windows for Consumers.
Are you seeing the power light to get on.
In case Windows won't even boot up, it might be a hardware issue and I recommend you to check with your PC manufacturer's support.

[#5]

Thank you.
Appreciate your good advices.
Chuenmon

[#6]

Welcome, glad it was helpful