Hi Qingjun,
Sorry for the inconvenience caused.
I assume you are using the VS2005 or Whidbey dragprovider style.It wont show the docking diamonds properly at runtime if you are using 64 bit machine.This is a known issue.We will try to fix this as soon as possible.
If you are experiencing any other issue,I am afraid I was not able to reproduce that.So Please modify the attached sample to bring the issue and send back to me.
Thanks for your feedback.
Regards,
Joy
sample38.zip