Skybox error in SDK 2013

Nothing changed in my map file since the 2009 SDK compile, it’s running with checkerboard textures for the sky. This error is in the compiler:

*** Error: Skybox vtf files for skybox/sky_day01_08_hdr weren’t compiled with the same size texture and/or same flags!
Can’t load skybox file skybox/sky_day01_08_hdr to build the default cubemap!
*** Error: Skybox vtf files for skybox/sky_day01_08_hdr weren’t compiled with the same size texture and/or same flags!
Can’t load skybox file skybox/sky_day01_08_hdr to build the default cubemap!

When using the LDR skybox textures, the skybox has a pink checkerboard. When using the HDR skybox textures, the reflective elements in the map have the checkerboard textures, even after running buildcubemaps. Any suggestions?

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