Windows 7: Desktop won't shut down and no Internet.

I'm hoping I can get some help. Two weeks ago there was lighting and a power surge.. My dell desktop must have been on because I have no Internet (and it was plugged into a surge protector). The storm also killed my wireless router and the cable modem. That was replaced but my desk top is still not able to connect. The icon that looks like a monitor has a red x and when I hit shut Down the computer goes into shut down the light on the tower goes off but then it immediately powers itself back on. I have unplugged everything from the back held the power button down for 30 seconds changed the power cord and still turns back on by itself.. So i guess the question is can i do this fix or does it have to be taken to a shop. Thanks in advance for the help!!

Without being familiar with what kind of resources you have, I'd try checking the power switch and it's connection to the mobo to check for fused connections. After that, I'd try to replace the power supply, temporarily, and powering it up.

570 Specs

Judging from the PDF, you don't even need a big PS.

Rightclick the Network connection icon in bottom right System Tray to run Troubleshooter.

See if Sleep and Hibernate work when you set them at 30 and 45 minutes in Control Panel>Power Options>Balanced Power plan>Advanced Settings>Sleep. You can also try manually triggering either from the Start Menu's Shutdown button's dropdown menu.

I would also reboot and tap the F8 key, select Repair My Computer, run a few Startup Repairs to see if it finds anything awry.

I did change the power cord and it still does not power down. My main concern is not being able to access the Internet. When I looked in device manager there is no network adapters. I'm not really that tech savy I just know this stuff from google. Oh and I did system restore. All this because of lightning.

Did you see the steps I gave you to perform just above?

Okay, I wasn't asking you to change the cord, but the actual power supply itself, inside the computer. It's the module that you're plugging the power cord into.

If you're not that tech savvy, I'm going to say that you should probably take this to a pro and let him/her find the issue. Playing with power supplies when you don't have an understanding of what's what is not a good idea in the first place.

If there is no Network Adapter showing up in Device Manager then your Ethernet adapter may have been fried and needs replacing.

You can check this by trying a wireless USB adapter in a USB port, run with that awhile to see if it otherwise functions correctly.

First, what a power supply does on power off is decided by a power controller - a separate item. The power controller could have hardware damage. Or a BIOS setting that says how it powers down might have changed. BIOS might be set to automatically restart. Or hardware damage to the controller might not power off at all.

Second, damage is classic of what happens when (for example) lightning strikes AC electric wires far down the street. That surge is incoming to every appliance. Most often damaged are appliances that also have an outgoing path to earth. Telephone and cable wires should already have best protection where their wires meet yours. So anything connected to those cables can be a best outgoing (and destructive) path.

To have damage means it must have both an incoming and another outgoing path. All other appliances (with or without adjacent protectors) also suffered the same incoming surge. But since routers, et al had a better outgoing path, then those other appliances were not damaged.

Damage is often on the outgoing path (internet side of router or computer's network interface card). Damage is sometimes made easier if a protector is adjacent to that electronics.

Third, a network interface card or motherboard chip (the outgoing path) is probably damaged. To say more starts by viewing lights that report each end of the Ethernet connection. Both on an NIC and router. A PCI network card probably is needed for the computer since Device Manager does not even see the original Network Interface's computer.

Four, learn of another and completely different device (also called a surge protector) that would have averted all that (and future) damage. And that costs less money. This other and so effective device works because it features a low impedance (ie 'less than 10 foot') connection to single point earth ground. Protectors without that short earth connection do not even claim to protect from the type of surge you have apparently suffered. Something you have learned the hard way.