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+8 votes
in Q2A Core by
I have a problem on my site where several users create a second account then upvote the posts on their main account. Is there any way to prevent this?

5 Answers

+4 votes

I don't think so, because clones are always a hard thing to prevent. Anyway, there are techniques which allow us to catch the more careless, by watching users that have the same IP at the same time. A tool to see where the user voted would be great, so you could compare if the votes went all to the same user (the main account). :)

Unfortunately I don't think any of these techniques are yet implemented in Q2A, but I think it's possible to create a plugin with such function. :)

–1 vote
try banning IP address.
–1 vote
You can just give a reputation point barrier for voting through Admin/Permissions    .   

Set it to a feasible value on your site.
+1 vote
A crazy solution would be like what google does. You ask users for phone number ( little crazy). they confirm with a code send to them via SMS. If people creates multiples email accounts they can't have multiples phones numbers ( Truth  to  be told i have two :) a smartphone and a stupidphone  : ) )
Here people may nave multiple numbers. Like in India most of the people having more than one mobile number. Since mobile manufacture companies now providing dual sim device. But some how you can control if not all.
Ahah , inefective solution though....
0 votes
How about this? Having some restricting rules. for example:

1) Prevent users to vote more than `x` specific user posts every day

2) Allow users to vote `x` specific user posts for every `x/5` getting voted from others (that works good mathematically, test it)

You can remove these rules for users anove `x` points.