This issue may happen on Designers hosted by non-case sensitive systems (some Windows versions for example).
After renaming a project, folder or file (mapping, metadata, process) from a given name to a different case:
- MyFolder => myfolder
- 010-metadata => 010-Metadata
... the underlying mappings cannot build anymore, wearing a red exclamation mark and/or leading to errors like these ones:
- Error during Multi process to one process (precompilation.oneProc) Watch console for more details
input file <build filepath> does not exist
- Failed to generate built files for platform:/resource/<mapping or process path>
A resource exists with a different case: '<mapping or process path>'.
When renaming "Folder" to "folder" (only changing the case), the non-case sensitive OS does not detect the change and does not apply the change to the hard disk.
This creates a difference between what is stored in the hard disk and what the Designer expects to find.
The solution is to rename in two steps: "Folder" => "dummy" => "folder". These are real name changes for a non-case sensitive OS, and therefore the issue will not happen.