Ayadam

Hi, I am wondering if any one can help me to resolve the following issue: In my proxy logs I keep having notifications informing me that a user tries all the time to access to a malicieus website. after verification it seems that this website is related to an adware. I have launched a full and very deep scan on this user's machine. I got nothing in the scan report, no malware detected. but the tries never stops. de you have any propositions for me ? BR,