Windows 7 PC froze in browsers, now won't boot

I have a Windows 7 PC that will no longer boot. Yes, I know it is running an outdated OS. I was planning on updating to W10 after tax season this year. This PC is on a network that is protected by a hardware firewall. Malware bytes was run and showed no problems a few days ago and the AV software Fprot is run frequently. The PC was shut down and all cables were unplugged for 5 days while I was out of town. When I came home I plugged everything in and it booted fine. I opened Firefox and the PC froze - wireless keyboard and mouse stopped working. I thought this was due to bad batteries, checked and batteries were low on power so put in new batteries. Still did not work. Rebooted PC and keyboard and mouse were working but PC froze again in Firefox. I wondered if the problem was Firefox so after next hard reboot I started chrome but same problem. Booted PC in safe mode with networking without a problem. Now when I try to boot PC and press F8 the bios hangs and does not load.

There is a chance that Windows was running an update in the background I did not know about one of the times when I forced a hard reboot by holding power button down.

I am a little concerned about ransomware or malware.

A little more about my setup. This PC is on a home network that includes a Windows 2012 server and a Synology NAS device. Everything sits behind a Juniper Networks SSG5 hardware firewall. I am on the only user on the network. Before I left on vacation I also shut down the server and NAS device. I powered them both up, but have not been able to check on their statuses as I usually access them using the W7 desktop.

Any thoughts on first steps to diagnose the source of the problem?

Really stumped here and in a bind. Thanks for your help!

 

Just a silly question - do you have a backup DVD or Thumb drive?
Alternately, you may need to restore the MBR.
Google to find necessary process for W7.

 

Hi thanks for your suggestion. I use Acronis Home to make image backups, not sure how recent the last backup was... yes I know. Is there a way to test for corrupt MBR? What are the symptoms of a corrupt MBR?

 

Update: I unplugged my ethernet cable and booted the desktop normally. It booted up fine, showing the desktop and saying could not connect all network drives. I think I am going to now run Malwarebytes and Fprot on the local drives and see if I am all clear. I think this rules out a corrupt Power Supply correct?

 

You did know that I was referring to the Master Boot Record? (MBR)
PSU was not on my mind but it seems you have isolated your problem to external peripherals.
You will need to diagnose whether your cable is faulty or your Network System.

 

Hi, sorry I was replying to two different forum posts. Thanks for understanding, Have an update. PC has successfully booted several times with the network cable unplugged and two Xdock drives removed. But the PC has locked up again shortly after windows loads. One time it locked when I inserted a USB flash drive (to install latest version of Samsung Magician to test the SSD), another time it hang when I opened Event Viewer to try and learn what is happening, a third time it hanged after I ran memtest and the PC rebooted and then hung before Windows loaded. The first two times it hung with Windows loaded I did not touch anything and the PC shut itself down after 2 minutes or so.

Does this make you want to focus on anything else? I may open tyhe desktop and look at the mobo to see if I see any obvious damage or a lot of dust accumulated. The mobo and most of the computer parts are 6-8 years old. I have an upgraded Power Supply, could it be going bad?

 

Have you run the comp in a "bare bones" condition?
This means all peripherals disconnected including printer/scanner etc.
No USB connections or Flash drives.
This should enable the comp to work as it was out of the box.
Did your Event Viewer show any exclamation points?
Graphics drivers updated?