.dsk file (Delphi Desktop File) saved by Delphi 2007 can't be opened by Delphi 7

Because I had to test Denomo on at least both D2007 and D7, I found a really annoying backward compatible problem in D2007.
If you save the project desktop in Delphi 2007, then when opening the project from within Delphi 7, Delphi will be in dead loop and have no responding. The only thing you can do is to kill Delphi in Task Manager.

To solve the problem, you only need to delete the .dsk file in your project directory before opening the project in D7.

If you have to switch between D2007 and D7 frequently, there is a method to not to delete the .dsk file each time when using D7. Just disable autosaving "Project desktop" in the environment options in your D2007 then D2007 won't save the .dsk anymore.

Note: The .dsk file is the UI settings of your project such as editor window size, position, etc. So it's safe to delete that file and let Delphi restore the desktop to default.