See: http://app.webinspector.com/public/reports/show_website?site=http%3A%2F%2Fvpn.caretower.com
and
https://www.sslcertificaten.nl/SSLCheck?domain=vpn.caretower.com
The certificate is self-signed. Users will receive a warning when accessing this site unless the certificate is manually added as a trusted certificate to their web browser. You can fix this error by buying a trusted SSL certificate
None of the common names in the certificate match the name that was entered (vpn.caretower.com). You may receive an error when accessing this site in a web browser. Learn more about name mismatch errors.
Common name: sslvpn.bg.caretower.com
Organization: Caretower
Location: ??, ??, ??
Valid from December 15, 2010 to June 6, 2016
Serial Number: 5619679894a9aa09
Signature Algorithm: sha1WithRSAEncryption
Issuer: sslvpn.bg.caretower.com
More issues: http://www.networking4all.com/nl/helpdesk/tools/site+check/report/?fqdn=http%3A%2F%2Fvpn.caretower.com&protocol=https
Site accepts connections with a low cipher suite!
Site is not being mentioned in certificate.
polonus