system
12
Take a look at http://answers.microsoft.com/en-us/windows/forum/windows_other-windows_update/windows-7-error-code-8007045d-cant-install-updates/03258f34-3f25-4134-b194-6c18b4acf521
You should take care of it before anything else. First, do a backup of your important data (data that, otherwise, can’t be recovered if anything bad happens). Then proceed with the instructions posted in that link.