Siemens Industry Online Support
Siemens AG
Entry type: FAQ, Entry ID: 35836051, Entry date: 04/27/2009

Why does the OS Login Box disappear sometimes in the background?

  • Entry
  • Associated product(s)

The reason for this might be incorrect settings in the Windows XP operating system.

Make the following settings to avoid this behavior.

No. Procedure
1 Go to  "Start > Control Panel > Regional and Language Options > Languages > Text services and input languages > Details" and then open the "Advanced" tab.
2 Clear the check box "Support extended text services in all programs".
3 Close all the windows and restart the PC.

Foreground, WinCC Login box

Security information
In order to protect plants, systems, machines and networks against cyber threats, it is necessary to implement – and continuously maintain – a holistic, state-of-the-art industrial security concept. Siemens’ products and solutions constitute one element of such a concept. For more information about industrial security, please visit