Note: The article below is specific to revocation errors and will not resolve the current error.
Some users report receiving this message when you first start up Xobni. Another symptom is that the sidebar does not draw completely, but remains a grey rectangle. We are trying to determine why it only affects a subset of Xobni users, but in the meantime you can either ignore the message (it should only appear one per session) or try the fix below (which requires a restart to take effect). See resources at the bottom for more on the error.
Confirm that your system clock and time zone settings are correct.
Open Internet Explorer (even if you normally use another browser) and [click the Alt button to show the toolbar menu], then navigate to Tools > Internet Options > Content tab > Clear SSL State button
Follow this linkand click the "Microsoft Fix It" button.
Run the MicrosoftFixit50191.msi that was downloaded in step 3.
The installer will prompt you to restart your computer. Please do so now for the changes to take effect.
NOTE: After trying the fix above you are still seeing the certificate revocation error, you are most likely behind a proxy. In this case, your only choice is to ignore the error message.