As you have installed 451 it appears there are issues connecting to servers
that are not running 451
and the latest Pure.
The advise we can give you is to try the
following:
If You Haven't Installed 451
Make a
copy your unrealtournamentsystem folder
Rename this folder copy to system.436
Install
the 451 patch
When you want to play on 436 servers rename your system
folder to system.451 and then rename your
system.436 folder to system
If You Have Installed
451
You can try doing the following.
Make a copy your
unrealtournamentsystem folder
Rename this folder copy to system.451
Install the old 436
patch
When you want to play on 436 servers rename your system
folder to system.436 and then rename your
system.451 folder to system
This problem is not a problem with a
patch.
Its not a "problem" with Pure either, its just how Pure is designed,
it checks the files and it see's you are using non-standard versions, as such it
assumes you are cheating.
Until the servers upgrade to 451
and a new official Pure is released and those servers use it,
this could be an issue for some time.