This is a common issue with Internet Explorer, Mozilla Firefox and Google Chrome. FYR, this security
error occurs due to PLESK or Virtualmin has provided a common SSL certificates by default. However, this will not create any additional security issues or breach of control panel security.
For Google Chrome:
Click to
proceed AnywayInternet Explorer 7
Click
Continue to this website (not recommended)Mozilla Firefox 2.x

Click
Accept this certificate permanently and on next windows click
OK