Unable to write the output of custom tool 'tool' to file 'file'. <reason>
The project system could not write the output of the custom tool to the specified file.
Provided that the file name of a custom tool's input remains unchanged, the output from a custom tool is written to the same file. This error occurs if the generated output is locked on disk.
To correct this error
- Restart Visual Studio and rerun the custom tool by right-clicking the affected file and selecting Run Custom Tool from the shortcut menu.
The generated file is probably out-of-date, because the project system could not update it.