Error when trying to launch PoE

Basically, i'll launch PoE through ISBoxer, then the window will semi-load. No program will be added to the taskbar, until I click the partially loaded window. At that point, if i click in the poe window that's loading, it will the display that message. After I hit ok, the window will then load. Basically, it works partially -- it tends to miss one or two of the instances i'm trying to load.

I usually get this error when another program is using d3d at the same time. For example, if im running/playing dota 2 while path of exile is trying to load itself it wouldn't be able to use that instance of d3d. I would look around to see what kind of other programs are running at the same time that are graphic intensive meaning that they need to use d3d at all times.

There is also other people who have reported similar problems on threads on the official path of exile forums. If the solution above doesnt apply then have a look at a few threads to see if there are any others as I dont think its a problem with isboxer.