Xitel INport Deluxe "ultra thread" Questions

...Thread ID 1728 When i start to uninstall Nero 7.3 ultra addition that time one error is coming and is that Internal Error custom Action DLL crashed on last call in function ...

i cant Uninstall / Install nero Internal Error: Custom action DLL crashed on last call function 'NeroAg_UnregisterComEx'. The installer must now exit. Crash Thread ID 1920 Current Thread ID ...