No game server is available to the authorization server (6)

Hi everyone, I would like to ask for the help of the community in a problem I have.
For 3 days while playing the game normally the game closed automatically and since then I get this error "No game server is available to the authorization server (6)" not if someone can help me since I have tried many things but I cannot solve my problem .

if i were you, i'd check these stuff to find out where the problem lies,
1.where does the error happen, at login screen?
2. check if files are updated / are you using the new launcher ?,
3. try creating a new account to see if the issue is related to account,
4.  when you start game via launcher open task manager and see if these processes are running,
https://ibb.co/F3pFXnh

hello thank you very much for answering I leave more details.
the message appears just before entering the character selector.
I log in normally and accept the terms.
my OS is windows 10 LTSC and I don't have external antivirus installed windows defender works very well for me.
I only get two of the 3 processes you sent as an example
and in my AION / bin32 folder I have the ".dll" "d3dx9_38.dll"
I attach an image of the problem.
https://ibb.co/rp321YP

when accepting the terms the client will establish a connection to the server, the problem seems to be it,
this is weird that you could play normally before then suddenly this happens, have you installed any software that may affect network or changed network settings?

@Administrator Attention please,

the only things installed on my PC are LOL, CS: GO, MSI Afterburner, Discord and FurMark.
of which only the "MSI Afterburner" was running to motivate my FP's