Hello! I was checking my Laptop's health this month and I was so surprised to see the Window's defender is not started. I clicked the "Start Now" button but a window says: "Windows Defender cannot be started". I checked the firewall. The Private and Public network firewall is off. I turned them on. I opened the windows defender again and clicked the "start now" button. A window appeared. Now it says: "The specific Service does not exist as an installed service. (Error Code: 0x80070424). I also tried using the "Windows Update". It's almost several months since I last got an update. And as far as I know, I set the option to "Notify me when new updates are available". I opened control center and windows update. But the windows update panel says: "Always install updates to enhance your computer's security and performance". I clicked the "Check For Updates" button. But another window says: "Windows update cannot currently check for updates, because service is not running. You may need to restart your computer." I checked the services. The Security Center has been started. But "Windows Defender" & "Windows Update" was not on the list! I scanned for malicious programs with my own Antivirus. I found some threats. But definitely that's a low threat and it wouldn't make changes on my system (because I always check each file before opening). Please help! 
~~~~Bryan James

~~~~Bryan James
My Computer
- Computer type
- Laptop
- Computer Manufacturer/Model Number
- Dell
- OS
- Windows 7 Ultimate 64-bit
- CPU
- Intel Mobile Core 2 Duo SP9400
- Motherboard
- Dell Inc. 0MR506 (Microprocessor)
- Memory
- 4.00GB Dual-Channel DDR3 (7-7-7-20)
- Graphics Card(s)
- Intel Mobile Intel 4 Series Express Chipset Family (Dell)
- Sound Card
- IDT High Definition Audio CODEC
- Monitor(s) Displays
- Generic PnP Monitor (1280x800@60Hz)
- Screen Resolution
- 1280x800
- Hard Drives
- 232GB Western Digital WDC WD2500BEVT-75ZCT2 ATA Device (SATA)
- Case
- Dell
- Keyboard
- Dell
- Mouse
- Dell
- Antivirus
- ESET NOD32 10
- Browser
- Google Chrome, Mozilla Firefox, Internet Explorer