There are 2 reasons why this happen:
1. If the product you have installed is either not original, or has not been installed properly and the version is a cracked one, which at times causes problem.
2. The other reason is that the perma link for this kind of program is either under some upgradation, or there is a server error.
However, I would agree with you that there are times, when the program does not reflect on SI, since no one has as of yet either categorised, listed or even checked the program.
If you are looking for ESET Smart Secutity:
http://eset-smart-security.software.informer.com/
If ESET Nod 32:
http://eset-nod32-antivirus-smart-security-x32.software.informer.com/
Hope this helps.
Cheers!