I'm currently using ENVSHADE. I just bought PTA and wanted to install it but I got shader file error because my shaders are not original P3D shaders. How do I go about installing PTA? There is a switch "Use PTA" in ENVSHADE but switching it doesn't solve the issue. I also found a ENVSHADE backup folder with supposedly P3D original files. Should I just copy those files over to P3D installation or what is the proper procedure to install PTA and then use either one (ENVSHADE or PTA) using the switch in ENVSHADE? I just don't want to mess something up.

Envshade should have an option to restore the original shaders.  If not, you can also reinstall the P3D Client to restore the default shaders.  Make sure to read the Prepar3d installation instruction sticky thread before you take this route to insure you do it properly.

5 hours ago, exeodus said:

Envshade should have an option to restore the original shaders.  If not, you can also reinstall the P3D Client to restore the default shaders.  Make sure to read the Prepar3d installation instruction sticky thread before you take this route to insure you do it properly.

It does. But wouldn't that make it unusable? I'd like to know how to install both, PTA and ENVSHADE, and use them one at the time using the "Use PTA" switch in ENVSHADE to toggle between them.