Problem with Dual Boxing on Premium Account

[Defiant 77]

Hi!

I got this problem when I try to open the second client.

I log in first on the account I have a premium account, then when I try to open a second client I get either of these two screens:

First one is login screen without the login box: http://prntscr.com/9ja3pt

Sometimes I get that one, sometimes I get just this error: http://prntscr.com/9jo41h

What can I do? My computer is pretty good, these are the specs: http://prntscr.com/9jo4zc

My video card is a GeForce GTX 680, so I don't think that's the issue.

What I already tried:

I opened the client from the same L2.exe I use on my main account and I installed the game from scratch on another hard drive and run the updater, with same results.

Thanks in advance for all the help you can provide

[Morim 112]

To discard. Are you using my mod?. If yes, normal or performance?

[Koll 1233]

Try to fully delete system folder, start updater and after update login in without any other addition files. Also please give info from History of the error it main part with info where is the problem.

Edited December 29, 2015 by Koll

[Defiant 77]

I'm using the mod, but I tried something different.

I resized the first window to a much smaller resolution and windowed mode.

It worked!