New post changing location in thread

[mtlcore]

Ok, I try posting and get this message:
The following errors occurred when this message was submitted

Then I hit refresh and I see my post appearing BEFORE the last post that I saw.

Example

Thread contains last post X, I want to reply to that post with post Y, hit submit and get that message, i refresh and I see post Y before post X......weird

and yes the message under it says:
This post is a duplicate of a post that you have posted in the last five minutes.

[Antivirus]

do you have the same problem when all mods/hacks are disabled?

[mtlcore]

yes same problem even with all mods disabled

also this problem came after i installed cyb prevent newbies from posting mod. i disabled it and still happening..

[Antivirus]

hmm... try disabling all the mods from here:
AdminCP->vbulletinOptions->Plugin/hookSystem (set this to no)

That might make a difference. Also, have you done any edits to any code in vbulletin files or are they all default (un-modified) versions?