Repository: godot
Issue: Project loses its default environment configuration
Labels: bug,topic:editor,confirmed,topic:3d

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https://github.com/godotengine/godot/issues?q=is%3Aissue
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**Godot version:**
<!-- Specify commit hash if non-official. -->
current tip
0565adb20ff01a758c5ae8e4534a2cb7f07952df

**OS/device including version:**
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Linux

**Issue description:**
<!-- What happened, and what was expected. -->
Open a project with a **textured panorama-sky** environment:

![screenshot from 2018-08-27 21-13-00](https://user-images.githubusercontent.com/4047289/44680859-32fe7a80-aa3f-11e8-8cad-613872195317.png)

```
; Engine configuration file.
; It's best edited using the editor UI and not directly,
; since the parameters that go here are not all obvious.
;
; Format:
;   [section] ; section goes between []
;   param=value ; assign values to parameters

config_version=4

_global_script_classes=[  ]
_global_script_class_icons={

}

[application]

config/name="Create New Project Test"
run/main_scene="res://Test.tscn"
config/icon="res://icon.png"

[rendering]

environment/default_environment="res://default_env.tres"
```
Close the editor and remove the cached files (I usually have .import/ in .gitignore) :
**rm -rf .import/**

Start the editor again:
**godot3 -e**

```OpenGL ES 3.0 Renderer: AMD Radeon HD 7700 Series (CAPE VERDE / DRM 3.26.0 / 4.18.1-041801-generic, LLVM 6.0.0)
ERROR: _load_data: Condition ' !f ' is true. returned: ERR_CANT_OPEN
   At: scene/resources/texture.cpp:469.
ERROR: _load: Failed loading resource: res://.import/skymap22_16f.exr-ce9b31538453c1bf4ce871fe24de66de.stex
   At: core/io/resource_loader.cpp:190.
ERROR: _load: Failed loading resource: res://skymap22_16f.exr
   At: core/io/resource_loader.cpp:190.
ERROR: poll: res://default_env.tres:3 - Parse Error: [ext_resource] referenced nonexistent resource at: res://skymap22_16f.exr
   At: scene/resources/scene_format_text.cpp:439.
ERROR: load: Condition ' err != OK ' is true. returned: RES()
   At: core/io/resource_loader.cpp:153.
ERROR: _load: Failed loading resource: res://default_env.tres
   At: core/io/resource_loader.cpp:190.
WARNING: cleanup: ObjectDB Instances still exist!
   At: core/object.cpp:2081.
```
```; Engine configuration file.
; It's best edited using the editor UI and not directly,
; since the parameters that go here are not all obvious.
;
; Format:
;   [section] ; section goes between []
;   param=value ; assign values to parameters

config_version=4

_global_script_classes=[  ]
_global_script_class_icons={

}

[application]

config/name="Create New Project Test"
run/main_scene="res://Test.tscn"
config/icon="res://icon.png"
```

![screenshot from 2018-08-27 21-15-54](https://user-images.githubusercontent.com/4047289/44680996-8ec90380-aa3f-11e8-9b4f-1cb03960486c.png)


**Minimal reproduction project:**
<!-- Recommended as it greatly speeds up debugging. Drag and drop a zip archive to upload it. -->
[default-env-test.zip](https://github.com/godotengine/godot/files/2325372/default-env-test.zip)