Thanks for the reply. The link about migration that you have suggested just mentions about the "New CyUSB.dll" and does not mention anything about the version number. It is just the version number that leads us to the confusion.
So would you say CyUSB.dll version 188.8.131.52 is the latest version of the dll? Could you also kindly comment on the thread safety aspect of this new dll, nothing is mentioned about this in the documentation. Thanks.
Did this get resolved? I am getting crashes in a multi-threaded application, that seem to be related to calls to GetOverlappedResult.
The problem is, I am using 4 EP, and without threads or with lock() in the C# application, the performance is really bad. So I need them.
I realize this post is old. However, for the sake of others who stumble upon this post, I had the same issue. There are several issues here. For one, this causes all kinds of issues with installers. The installers will refuse to overwrite the old CyUSB.dll because the new DLL has a lower version than the "old" one. I had to go in a rename the whole CYUSB.dll and re-export it with a different name so that the installer would think it's a different dll (therefore, removing the old one and installing the new one). Secondly, there is a SERIOUS regression in the CyUSBEndPoint.xferData implementation. All three of the managed buffers used are not pinned properly. When the GC moves those managed buffers during async operations, it corrupts the managed heap. I just spent the last week tracking down that bug. I've decompiled the 1.2.2 version and the 3.4.7 version and can verify that all buffers were properly pinned in the 3.47 version and not in the 1.2.2 version. I ended up creating an Extension method that pins all of the buffers for the duration of the xferData method.