Cannot connect to server ?

[Worst_Driver]

I have a problem getting online in GT5 since the last three days, I can only play offline. The weird thing is that I can play online with the rest of my games without a problem.
When I start GT5, I get a black screen written Gran Turismo 5 for about a minute and then I get an error screen, so I sign out of PSN and then I can play, but only offline.

Anyone else have this problem or have experienced something similar ?

 

[Worst_Driver]

A connexion to the server could not be established (ID=1:531)

 

[PAPPACLART]

Have you tired clearing system cache via GT5 network options, may help?

 

[Worst_Driver]

Nevermind, I just disconnected my router and now everything is fine.