Can't update CIS

I have CIS without the antivirus. I installed version 5.5 about 6 months ago and initially it was easy to update. I just clicked on ‘check for updates’ in More. However, for some time now this has not worked. I click on ‘check for updates’ and nothing happens. Any idea why this is?

Hi N01paranoid and welcome,
It would be worth trying the instructions found here.

That failing I would suggest an uninstall/reinstall as V5.8 is now the latest.
Found here.
Good luck.