i got this problem 4 days ago i think since i upgraded my pet 2(boar)
every time i try to open my bank i got this message
and
Data Process , Try Again
i tried 2 open the bank from different Bankers ,change channel ,log-out ,exit the game ,unpatch ,re-install the game
and the same thing
but the other character in the same id and all other character open the bank normally
This is a server issue,not a client one,i had the same one b4 thankfully for me it was a char that i didnt want and i deleted him...you need to contact wasabi for it,it caused from an item that you shouldnt have at bank,as i had found in past there is a way to duplicate items but they had fixed it,so it might be a faulty duplicate...or it might be a bad synchronization with server for certain item that is super rare or has faulty stats etc...other way is to wait for maintence to see if it will be fixed...
ps.(i aint playing the smartbottom or hacker,just trying to give the idea of an issue).