Tanmay,
Do you have HTTPS detection turned on for the Endpoint Agent?
You will need to have HTTPS turned on in the Agent Configuration section.
Also what browser are you using? I believe that there might be an issue with newer versions of Firefox for HTTPS detection.
Also take a look at this article, looks like Dropbox might be the issue.
https://kb-vontu.altiris.com/display/1n/kb/article.asp?aid=56716&n=5&s=
Hope this makes sense.
If this solves your questions please marked as solved.
Ronak