This thread started here:
but It was marked as "answered" without a clear solution. Although many people probably found a fix elsewhere, I opened a new thread because this can be useful for somebody.
Some devices, like the Logitech G25, fail to initialize Force Feedback when using the DirectInput Samples for Managed Code. Others, like the Logitech Driving Force Pro, don¡¯t present this behavior.
I talked with Logitech¡¯s engineers and we found that it¡¯s due to a couple of bugs in the Microsoft DirectInput Samples. The whole thing is explained in my blog:
Hope it helps.