Quelle: UESP.net
Problem
Oblivion crashes on alt-tab, the windows key etc. It also crashes on instant messenger notification, update confirmation request from my antivirus etc.
Cause
The Alt-tab problem is covered in Readme of the game - the game may, but doesn't have to work correctly after you switch to other app. The problem though is that Alt-tab is not the only method of switching Windows focus to other application, and all the others cause the same problem.
Workaround
Keep your task manager (opened with ctrl+shift+esc) open in the background while playing. After switching out of Oblivion, do not use alt+tab or the task bar to switch back. Instead select the application in your task manager and use the 'Switch To' button. This will restore the window on your desktop but nothing renders. Now click the taskbar to switch back to Oblivion. Works on WinXPSP2 with an ATI card and latest official Catalyst package. Sometimes has to be tried a few times, but has never failed. Alternatively, open any background applications you may want to Alt-tab too (eg: this website) before you start playing. Do not close these background apps whilst playing, or the game will freeze up.
Solution
Don't do it. Switch everything unnecessary off.
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