Delphi projects always opens same .pas files

delphi, delphi-xe2

Solution

Just close Delphi, delete .dsk file, reopen project. Be sure to select autosave options properly in Tools -> Options -> Environment Options.

Problem

Every time I open the project, it opens the same `.pas` files. Even if I close those files and open some other files, when I close and reopen the project, the same original files will be opened. How can I solve this?

Original source