Always Goes Into Sleep Mode At Shut Down

I restored my laptop to factory settings a few days ago using the built in Dell Backup and Recovery Manager. This isn't the first time I've done this but something happened. Now, whenever I shut down the computer using Start > Shut Down button (on the start menu) it goes into sleep mode. After the screen goes black (powers down) the actual on/off power button on the laptop continuously blinks on and off. It never used to do that before. Prior to this restore whenever I clicked Start > Shut Down button the screen would go black, everything would power down, and the laptop power button never blinked. Here's what I've checked so far:

1. The Shut Down button does say Shut Down. I right clicked the Start button > Properties > Power button action: and selected between Switch User, Log Off, Lock, Restart, Sleep, Hibernate, Shut down. The name of the button changes to whatever I select and every other option works except for Shut Down.
2. I disabled Hibernate from an elevated command prompt by typing: powercfg -h off
3. I checked Advanced Power Options and the default action for the Start menu Shut down button was showing Shut down. I opened the settings tree and selected Power Buttons and Lid > Power button action (which refers to the Start menu shut down button, not the laptop on/off power button) > Setting > and toggled through the various settings finally selecting Shut down and OKing my way back out of this dialog box. Still no joy. Whenever I click Start > Shut down button it still goes into sleep/hibernation and the laptop on/off power button blinks.
4. I checked system settings through Control Panel > Power Options > Choose what the power buttons do. This opens a dialog box that allows you to select what happens when the Start > Shut down button is clicked when the laptop is on battery power or plugged in. Again, these options were set to shut down but I toggled though the options, re-selected shut down, saved changes, OKed my way back out. Didn't help.
5. I checked the registry here:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
and verified the Start_PowerButtonAction hexadecimal value data is 2 (Switch User = 100, Log Off = 1, Lock = 200, Restart = 4, Sleep = 10, Hibernate = 40.)
6. I checked Device Manager and all devices are functioning correctly. For those devices with a "Power Managment" tab and the option to "allow the computer to turn off this device to save power" I configured the devices both ways (option checked and option UN-checked.) Made no difference, laptop still shut down in sleep mode.
7. I reset BIOS to default settings.
8. All Windows updates are installed and all drivers are current.
9. I also went to Group Policy Editor (gpedit) and changed the start menu power button by making Shut Down the default option with no way to change it to anything else (user configuration > administrative template > start menu and taskbar > select: enabled > select: shut down.)
10. I've done a clean boot using msconfig. I disabled half the services, shut down the laptop, it went into sleep mode. I enabled those services and disabled the second half. Still went into sleep mode on shut down.
11. Several diagnostic tests show 100% pass with no hardware issues.
12. My last effot was to do a format/clean install (not a factory restore.) Laptop still goes into sleep mode at shut down.

Nothing has solved this problem. Does anybody have any other ideas of what's wrong and why my laptop insists on going into sleep mode? Sorry for making this so lengthy. Just wanted to hopefully avoid sugggestions of things I've already tried.

Well, all I got is this. Try power options and advanced power options, check both options for plugged in and battery. Other than that, if clean install and going through all of these actions doesn't help, you might try a small square of electric tape to fit nicely over that blinking light. Someone may come up with a better idea

Tried advanced power options in # 3. Didn't fix the issue. But I like your suggestion about the electric tape. Once used the same fix for a check engine light that just wouldn't reset. :roflmao:

Buddy m not sure if your issue fixed now but solution for this problem is Motherboard replacement, Please let me know in case if the issue was fixed with any other step.