The Mana World Forums

It says "trade cancelled for unknown reasons" , it started to happen to me yesterday and even if i re login it wont fix.

Having same problem here also.

my mule have also, but Swimmy and Buster doesn't. strange :/

Sometimes happens. I've noticed, that sometimes you need to try several times, before succeed.

The person you're trying to trade with will have to relogin. We'll get this fixed for the next server update.

So where does the bug reside, sever or client, or is it a combination? Other than restarting every time one needs to trade, is there any preventative measure a player can take?

It's purely server side. The only thing you can do is not shop and have the other person trade you. This will be fixed with the next server update.