yes, the others tray icons appear!
ufff, after some reboots i could isolate the application that caused the error. since i'm a java me developer i have the java me sdk 3.0 installed on my notebook and while system booting the system try to start the device-manager.exe of the java me. after deactivating this app in the ccleaner the error desappered.
the real cause is yet unknown, since i could start the device-manager.exe without problems and an icon appeared. i will try to uninstall and reinstall the app again.
anywhy, thank you a lot for the strategy with ccleaner.