The security certificate has expired or is not yet valid

hi friend, i do it and it show this to me

Path #1: Trusted

1 Sent by server http://www.mydomain.com

2 Sent by server GlobeSSL DV Certification Authority 2

3 In trust store USERTrust RSA Certification Authority Self-signed

Path #2: Trusted

1 Sent by server http://www.mydomain.com

2 Sent by server GlobeSSL DV Certification Authority 2

3 Extra download USERTrust RSA Certification Authority

4 In trust store AddTrust External CA Root Self-signed
Weak or insecure signature, but no impact on root certificate

I managenment my web site, what i need to do?

Thanks!