Hello Karthik, > For the creation of handle it is working File, Now if i try to create > another handle with ... > This is failing with ACCESS_DENIED To have an ability to create more than a single handle, device driver must support creation of multiple instances. For each CreateFile call, the IRP_MJ_CREATE request is sent to the driver. Many drivers allow only a single open/create request, and will fail subsequent requests until the handle is closed. Regards, Eugene ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/