Cpanel Security

[FirefoxRocks 0]

I have had this issue forever now since I have Xisto Hosting but I'm wondering if it is safe.

In Internet Explorer the certificate error tab appears when I try to access http://forums.xisto.com/no_longer_exists/. In Firefox 3.5, this shows up:

portal.trap17.com:2083 uses an invalid security certificate.
The certificate is not trusted because it is self signed.
The certificate is only valid for gamma.xisto.com.
The certificate expired on 05/06/2009 1:15.

(Error code: sec_error_expired_issuer_certificate)

So is it safe to use cPanel without worrying about other sites looking at my data or what?

[yordan 10]

The certificate is only valid for gamma.xisto.com.

This is correct, you only want to access gamma.I don't think other sites can see what you are doing under your capanel, the warning message says that the certificate mechanism is not controlled being fully secure, and nothing says that what you are doing really concerns your site.
However you can check that the files you are sending are really sent to your own website, and no money-related infos are given to your cpanel, so nothing dangerous can occur.
The error message simply says that Microsoft Internet explorer does not really love the way your browser security settings manage this certificate.
On my IE8 Xisto cpanel certificates are accepted correctly, but my office's mail certificates are not Microsoft-compliant and I had to go back to IE6.

[FirefoxRocks 0]

Then why is the certificate expired?

[yordan 10]

Then why is the certificate expired?

Probably because you connected several times the same day, the new certificate did not replace the old one.If you feel uncomfortable with that, the best thing is to open a ticket at Xisto - Support (https://support.xisto.com/supporttickets.php) mentionning this topic.
By the way, do you still have this problem? Or does it disappear after reboot ? Personally I don't have such messages.