Why Do I Keep Losing Connection with Google?

I'm getting this error message a lot:

Error loading data. GDataauthErrorAuthorizationInvalid Credentials

I've checked with my hosting several times, and they always report the server is in the correct time. But, probably once a week or so, the entire site loses connection to Google Analytics. I can check analytics on an app just fine -- but not on the site.

What is this error and why does it keep happening?