I have an annoying problem with my iMac 8.1 which has only one processor: a 3.06 GHz Intel Core 2 Duo Processor. The machine also has two cores that have 6MB L2 and 4 GB memory. I operate with OSX 10.6.8. The machines other specifications are: Bus speed of Bus Speed: 1.07 GHz, Boot ROM Version IM81.00C1.B00, SMC version 1.20f1, model: Hitachi HDS721075KLA360. All of a sudden, the machine can only have only one open application at any given time and any other open application disappears from the screen.
Although other open applications can be viewed through use of the Tab-command, the other operation immediately disappears. At no time do I use expose or spaces features. It is so annoying and inconveniencing. Could know the cause and solution for my problem? Please help.