I was getting this error and found no solution for it online but I figured it out myself so I thought I would share it. The full error message was:
Roboform was unable to connect to RoboForm Online Server:
Cannot connect to https://online.roboform.com/users/modtang: SSL: Cannot load trusted root certificates from 'C:\Program Files\Siber Systems\AI RoboForm\cacert.pem'; error: 02001002:system library:fopen:No such file or directory[2001002 (fopen('C:\Program Files\Siber Systems\AI RoboForm\cacert.pem','r'))
error:2006D080:BIO routines:BIO_new_file:no such file[2006d080]
error:0B084002x509 certificate
routines:X509_load_cert_crl_file:system lib [b084002]
If you are getting this error you need to download the missing certificate and put it into your RoboForm installation directory. I have zipped the needed file and uploaded it to RapidShare so it's easy to find.
http://rapidshare.com/files/415229055/cacert.zip
If you need assistance, or if the above link doesn't work, you can leave me a reply here and I will help you out.