For those unfortunate enough to still be deploying Windows 7, I implore you to ensure your workstations have at least one of the following updates to save yourself much pain:
These updates address a situation where the Windows Update client causes the machine to grind to a halt. This can be especially troublesome if you’re beginning to manage your environment with SCCM (even if you’re only deploying SCEP updates) as SCCM’s updating mechanism relies upon the Windows Update client.
So, before you deploy any updates to Windows 7 clients, ensure the machines have the above KB’s installed!
For more information, follow this TechNet blog post: https://social.technet.microsoft.com/Forums/windows/en-US/4a782e40-bbd8-40b7-869d-68e3dfd1a5b4/windows-update-scan-high-memory-usage?forum=w7itproperf&prof=required