Yesterday my HTC Tattoo (with software based on Donut) started giving me "No connection Retry" errors for Gmail, YouTube, Google Reader, Market and anything else that requires sign in with Google credentials.
After doing a "Clear data" on the Gmail app I get another message,
There was a network error while trying to sign in to email@example.com. Retry now or press the back button to cancel
Whatever "network error" there is, does not stop me from using the web browser. Indeed I am able to logon to the mobile (and unfortunately buggy) Gmail web app from the browser. I will note that I get "Security warnings" about the certificate for google.com.au: "the name of the site does not match the name of the certificate" when I logon via the web, although I saw that message months back and have been able to use my apps until now.
Any idea what could have triggered this? I've not changed my google account credentials, or switched SIM card, or done anything that I think could make it my fault.