Thank you Mr.Kayla.
This screenshot is at north part of Biwako lake, altitude is 3000 feet.
I used photo scenery, but using P3Dv4.5 default scenery, same rectangle is appeared.

Best Regards
Yutaka Mito

Dear Every body

Thank you for kind advice.
I want to add a screenshot of Biwako lake, but I do not know how to add it to this forums.
Rectagle appears at the north part of Biwako lake, flying altitude is 6000 feet.

Yutaka Mito

Hi
When I fly over the Biwako lake P3D v4.5 default scenery, there is a large rectangle edge on the surface of the lake.
Is there any solution?
Yutaka mito

Dear Sir.
Thank you for your kind advice.
I can uninstall and reinstall v4.1.

Best Regards
Yutaka Mito

Dear Sir. In order to uninstall v4.0, I uninstalled P3D using Windows setting menu by manual for each 4 programs , Client.msi Content.msi and Scenery.msi. May be, I made a fatal mistake. Client and Scenery msi file only uninstalled. After that, I met 0x80070643 error at Repair or uninstall program. ...

Dear Sir There are many trouble with v4.1, so I tried reinstall. But the process is stopped with error log as follows. My system is Windows10 Japanese version, Geforce GTX970 with 4GB video memory, Intel i7. Please advice me. Best Regards Yutaka Mito Error log is; [2488:034C][2017-11-15T09:10:16]i00...