Can’t Sign In to Skydrive Using Windows 8 App

I've been using the desktop client for some time with no issues.  Today I can't sign in, I'm getting an error message telling me to check my Internet connection, which is fine.  I've uninstalled the app and downloaded and installed the latest version, but it made no difference.  Can you help, please?

I ca connect with no problem using the web and my tablet.

thanks