Hi Randy,
It seems that, you need assistance with updating the Microsoft Security essentials.
We need some more information to assist you with the issue, please answer the following.
- Do you have any other installed antivirus application on your computer?
- Is this issue confined to updating the Microsoft Security essentials?
- Did you face any issue with installing other Windows Updates?
Refer to the following link, which has enough information to work on updating the Microsoft Security essentials.
Unable to run MSE updates, getting error 0x80070424.
Disclaimer: The Reset Internet Explorer Settings feature might reset security settings or privacy settings that you added to the list of Trusted Sites. The Reset Internet Explorer Settings feature might also reset parental control settings. We recommend that you note these sites before you use the Reset Internet Explorer Settings feature.
If the issue confined to Windows updates, refer to the following link.
Error 0x80070424 ocurs when you use Windows Update, Microsoft Update, or Windows Firewall.
http://support.microsoft.com/kb/968002
You can manually download and install the full engine/definition update from here:
https://www.microsoft.com/security/portal/Definitions/ADL.aspx
Hope this information helps. If you need further help with Windows; I would suggest you to reply with more information, we’ll be glad to assist you!