[Dolan.]

I don't want to disable negative reputation completely, but I do want to revoke this privilege from a usergroup.
How do I do it? Is a plugin needed?

This is for myBB.

[Traumax3]

I don't want to disable negative reputation completely, but I do want to revoke this privilege from a usergroup.
How do I do it? Is a plugin needed?

AdminCP > Users And Groups > User Group You Want > Edit > Users And Permissions > Uncheck "Can Give Reputation"

[Dolan.]

It'd help if you specified which forum platform you are talking about...

Sorry about that, updated the OP.
I'm using myBB.

[Gory]

Gravedigging because I could do with an answer.

[Gory]

Edit the reputation.php file.

Find (without quotes):
"if($mybb->settings['negrep'])"

And change it to (without quotes):
"$group = "3,4,6,8";
$groups = explode(",",$group);
if($mybb->settings['negrep'] || in_array($mybb->user['usergroup'],$groups))"

I tried that, it works to an extent. It gives me the option to give a negative reputation to a user when I have negative reputation disabled, where as before it wouldn't.
However when I actually click to give the rep I get "The administrator has disabled negative reputations.".

[Browithaquestionmark]

<if $GLOBALS['mybb']->user['usergroup'] >= GROUP ID HERE then>
Put that in the template for the reputation prompt over neg reps

edit: oh lol this is from 2k12. Back when mybb 1.6 was still going. oh great.