Why do you need to click the link?
With help from this post
#include <IE.au3>
Const $navOpenInNewTab = 0x0800
Local $oIE = _IECreate("http://www.autoitscript.com/site/")
Local $oLinks = _IELinkGetCollection($oIE)
For $oLink In $oLinks
If StringInStr($oLink.href, "/forum/") Then
$oIE.Navigate2($oLink.href, $navOpenInNewTab)
ExitLoop
EndIf
Next