MPC-HC playback some videos appears black-border only in fullscreen

[MeteorRain]

One of my friend havs encoded a video in 704*528 and another 640*480, soon find it appears to have thick black-border on top and bottom when playback only in full screen of 1024*768, while no black-border when window mode.

but he has some other videos in such resolutions w/o the border problem.

only appears in MPC-HC (casimir-mod v1.0.11.0), but everything normal in MPC (v6.4.9.0).

is there any idea what happened?

regards
MeteorRain

[foxyshadis]

Reset the pan & scan options, make sure video frame is set to "touch window from inside" and "keep aspect ratio". Check that the renderer is Overlay, VMR9 renderless, EVR, or Haali's. Alternately just reset your MPC options completely by deleting the registry key and any ini.

[appyton]

How to effectively delete MPC registry key and any ini? thanks. Using Vista.