Webroot detected and removed this virus: Trojan.dropper.gen. How did I get this virus? Thanks

Hello there, welcome to the Community!
 
It could have come in to your computer any number of ways.  Email, a bad website, a bad download, etc etc etc. The important thing is that as it came in, Webroot identified it and killed it.
 
 :)

Thanks for the quick reply. Webroot works great.

I would personally have Webroot support look into this detected file and make sure it is malicious and not a False Positive. Although i have found them to be quite rare, i have seen false positives from Webroot. If something gets detected on my machine, before i take any action against it, i check to see what the file is associated with, its location ect. Then i use a on demand scanner "second opinion scanner" and other forms of file verdict to make sure it is malicious. If i find it to be a false positive, i submit it to Webroot so that they can add it to their database. 
 
In this case where you are unsure how you got it, i would submit a support ticket and let them look at the logs to make sure it was indeed a Trojan.dropper.
 
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