Danny,
Click the link in event viewer and save the file.
Right click to open.
Right click again on the file, choose extract, in my case to the desktop. Choose 'save' in the pop-up.
On the file on the desktop, right click, and choose 'Intall CTL'
The Install wizard should now be open. I used the automatic option. Follow the 'next' and 'finish' buttons as appropriate.
My own personal feeling are that there is an error in the root certificate, and it will take a wee while for it to get sorted. I personally would't bother, it didn't clear the event errors, but at the same time, it's not had any detrimental effect on my machine.
Hope this all helps.
John