"Application not found" when opening Control Panel

All, I searched the support forum for "Windows Explorer Replacement" and found 329 entries and went back to page 11 of 17 (2008) to find a similar post without success. Also be aware that I'm using the German version, however I can't imagine the problem is related to that german version.
So, when replacing the Windows Explorer with DO any access to the control panel leads to [www.daniel-paschmann.de//images/errmsg.jpg] (please see the screen shot of the error window) --> "Anwendung nicht gefunden" / "Application not found".
Using the original WE by selecting option "Don't replace Windows Explorer" in the DO menue "Settings" a minute later everything is ok.
And, I've been using this 64 Bit netbook for 3 years now: This problem appeared this early spring.
My DO is the
Anyone an idea? Help appreciated.
BTW: searching for this error message in non DO related forums is really interesting. Many people seem in dispair - nobody can really offer help.
Thanks. Danny

Please give this a try, it looks like a fix for the same issue:

winhelponline.com/blog/fix-f ... windows-7/

Jon, Thanks for your help, however, it did not solve the problem, which is still there without any change.
There are two cases:
In cases where the system tray would call the explorer directly (such as for "printer", "games", "Own documents", ..) an error window pops up with the title "Explorer.exe" and the error message "Application not found".
In the other case (calling the system tray from Windows Start) first that message box which I posted initially appears, clicking "Ok" then gets me the "Application not found" box as above.
Still disabling DO as expolrer substitute fixes the problem, which of course is not my favorite solution.

This thread has some other suggestions for a similar issue:

[ul][li]Control Panel and DO 10[/li][/ul]