Windows Update cannot check for updates

[Cullism]

When I attempt to check for new updates I end up with the message "Cannot check for updates" the upadte error is 80070002. I have followed the instructions provided when I press the Get Help button but to no avail. I also tried following the advice given in an earlier post (Re-registering the Windows Update DLL), again without success (Note: regsvr32 wuaueng1.dll and wucltui.dll failed to load).

I have also tried downloading updates via Lenovo Care but receive the message "Unable to connect to the proxy server".

It has been suggested that a freeware registry cleaner I downloaded and ran may have told my computer not to update. It may be significant that Windows Restore also won't work, citing an "unspecified error". I was able to do a restore via Lenovo Care but my Update problem persists.

Lenovo Support suggested that I might have to reformat the hard disk and start from scratch, but I would rather avoid that if I could!

[Murf]

Welcome to CTH

Follow these STEPS (http://support.microsoft.com/kb/910336/en-us)may help:

[Cullism]

I followed the steps but when I entered ren SoftwareDistribution SDTemp I was told that "The process cannot access the file because it is being used by another process". I seem to remember trying this once before and being told that I wasn't the Administrator.

Is it significant that System Update in Lenovo Care tells me that it is unable to connect to the proxy server?