Why Bdis 2009 Unable To Detect Trojan

Today I perform a deep scan of my laptop using BDIS 2009. Result came out fine except for 2 files which was not scan due to password protected.


Out of curiosity I perform a Bitdefender online demand scan of my laptop and it detected a trojan file from one of the file inside 7 zip, it then proceed to delete this file.


My question is what had happen, why BDIS 2009 is unable to detect the trojan file while online scan is able and how reliable is BDIS 2009, I'm begining to have doubt about this product.


Hope someone is able to explain what had gone wrong with BDIS 2009.

Comments

  • Hello Ronald,


    Did you verified when the latest successful update took place? That might be an possible explanation that the signatures for the online scanner were a recenter version then those on your computer.


    Did you changed any of the properties of the deep scan? I mean did you right clicked on it and choosed properties,custom and changed one of the options.


    Another possibility is that the online scanner has higher heuristics which sometimes can cause false positivs secondly the online scanner detects also corrupt virus files.


    Kind regards,


    Niels

  • Hello Ronald,


    Did you verified when the latest successful update took place? That might be an possible explanation that the signatures for the online scanner were a recenter version then those on your computer.


    Did you changed any of the properties of the deep scan? I mean did you right clicked on it and choosed properties,custom and changed one of the options.


    Another possibility is that the online scanner has higher heuristics which sometimes can cause false positivs secondly the online scanner detects also corrupt virus files.


    Kind regards,


    Niels


    Niels,


    Thanks or your reply,


    I did check for the lastest updates before I did the scan.


    As for the deep scan it's all at default setting.


    I guess it like what you said the online scanner might be giving false positives.


    Anyway to be on the safe side I think will do a online scan every quarter.

  • also you can upload those files to virustotal or jotti for more verifications