How to interpret .otares file in Delphi XE2?

Question

There is a new file [project-name].otares created in Delphi XE2.

The wiki says:

File with unknown resources generated during upgrade of pre XE2 project. (Unknown resources are resources that are not included in the build configuration, like version info, icon, manifest or styles.)

How I can read this binary file meaning. Which resources exactly haven't been migrated?

After opening the otares file with ResEdit tool I displayed the information I needed:

Answer 1

您可以在资源编辑器中打开该文件，例如： XN Resource Editor ， ResEdit ， Resource Hacker ，Visual Studio等。

Answer 2

Somehow such a file was created in a new package of mine by Delphi 11. A warning was being issued at compile time that duplicate resource from .res file was discarded. Also at other Delphi 11 installation it didn't build anymore without an error message (just that warning which didn't cause build issue at the other project).

Solution was to right click the project and pick "View source", then remove the {$R *.otares} that had been placed before the {$R *.res} in the .dpk file (for app project instead of package project it would be the .dpr file)